molenda.net/lib/php_text.txt

Booleans
The bool type only has two values, and is used to express
  a truth value. It can be either  or .
Syntax
To specify a bool literal, use the constants  or
   . Both are case-insensitive.
Typically, the result of an operator
   which returns a bool value is passed on to a
   control structure.
Converting to boolean
To explicitly convert a value to bool, use the
   (bool) cast. Generally this is not necessary because when
   a value is used in a logical context it will be automatically interpreted
   as a value of type bool. For more information see the
   Type Juggling page.
When converting to bool, the following values are considered
   :
the boolean  itself
the integer
     0 (zero)
the floats
     0.0 and -0.0 (zero)
the empty string "",
     and the string "0"
an array with zero elements
the unit type NULL (including
     unset variables)
Internal objects that overload their casting behaviour to bool.
     For example: SimpleXML objects
     created from empty elements without attributes.
Every other value is considered 
   (including resource
   and NAN).
-1 is considered , like any other non-zero
    (whether negative or positive) number!
Casting to Boolean
Integers
An int is a number of the set
  ℤ = {..., -2, -1, 0, 1, 2, ...}.
Floating point numbers
    Arbitrary precision / BCMath
    Arbitrary length integer / GMP
Syntax
Ints can be specified in decimal (base 10), hexadecimal
   (base 16), octal (base 8) or binary (base 2) notation.
   The negation operator
   can be used to denote a negative int.
To use octal notation, precede the number with a 0 (zero).
   As of PHP 8.1.0, octal notation can also be preceded with 0o or 0O.
   To use hexadecimal notation precede the number with 0x.
   To use binary notation precede the number with 0b.
As of PHP 7.4.0, integer literals may contain underscores (_) between digits,
   for better readability of literals. These underscores are removed by PHP's scanner.
Integer literals
Formally, the structure for int literals is as of PHP 8.1.0
   (previously, the 0o or 0O octal
   prefixes were not allowed, and prior to PHP 7.4.0 the underscores were
   not allowed):
The size of an int is platform-dependent, although a maximum
   value of about two billion is the usual value (that's 32 bits signed).
   64-bit platforms usually have a maximum value of about 9E18.
   PHP does not support unsigned ints.
   int size can be determined
   using the constant PHP_INT_SIZE, maximum value using
   the constant PHP_INT_MAX,
   and minimum value using the constant PHP_INT_MIN.
Integer overflow
If PHP encounters a number beyond the bounds of the int
   type, it will be interpreted as a float instead. Also, an
   operation which results in a number beyond the bounds of the
   int type will return a float instead.
Integer overflow
Integer division
There is no int division operator in PHP, to achieve this
   use the intdiv function.
   1/2 yields the float 0.5.
   The value can be cast to an int to round it towards zero, or
   the round function provides finer control over rounding.
Divisions
Converting to integer
To explicitly convert a value to int, use the (int) cast.
   However, in most cases the cast is not needed, since a value will be automatically
   converted if an operator, function or control structure requires an
   int argument. A value can also be converted to
   int with the intval function.
If a resource is converted to an int, then
   the result will be the unique resource number assigned to the
   resource by PHP at runtime.
See also Type Juggling.
From booleans
will yield 0 (zero), and  will yield
    1 (one).
From floating point numbers
When converting from float to int, the number
    will be rounded towards zero.
    As of PHP 8.1.0, a deprecation notice is emitted when implicitly converting a non-integral  to  which loses precision.
Casting from Float
If the float is beyond the boundaries of int (usually
    +/- 2.15e+9 = 2^31 on 32-bit platforms and
    +/- 9.22e+18 = 2^63 on 64-bit platforms),
    the result is undefined, since the float doesn't
    have enough precision to give an exact int result.
    No warning, not even a notice will be issued when this happens!
NaN, Inf and -Inf will always be zero when cast to int.
Never cast an unknown fraction to int, as this can
     sometimes lead to unexpected results.
See also the warning about float
     precision.
From strings
If the string is
    numeric
    or leading numeric then it will resolve to the
    corresponding integer value, otherwise it is converted to zero
    (0).
From NULL
is always converted to zero (0).
From other types
The behaviour of converting to int is undefined for other
     types. Do not rely on any observed behaviour, as it
     can change without notice.
Callables
A callable is a reference to a function or method that is passed to
  another function as an argument.
  They are represented with the callable type declaration.
Some functions accept callback functions as a parameter, e.g.
  array_map, usort, or
  preg_replace_callback.
Creation of callables
A callable is a type that represents something that can be invoked.
   Callables can be passed as arguments to functions or methods which
   expect a callback parameter or they can be invoked directly.
   The callable type cannot be used as a type declaration for class
   properties. Instead, use a Closure type declaration.
Callables can be created in several different ways:
Closure object
containing the name of a function or a method
containing a class name or an object
     in index 0 and the method name in index 1
implementing the __invoke()
     magic method
A Closure object can be created using
   anonymous function syntax,
   arrow function syntax,
   first-class callable
   syntax, or the Closure::fromCallable method.
The first-class
    callable syntax is only available as of PHP 8.1.0.
Callback example using a Closure
A callable can also be a string containing the name of a function or
   a static method.
   Any built-in or user-defined function can be used, except language constructs
   such as: array, echo,
   empty, eval,
   isset,
   list, print or
   unset.
Static class methods can be used without instantiating an
   object of that class by either, creating an array with
   the class name at index 0 and the method name at index 1, or by using
   the special syntax with the scope resolution operator
   ::, as in 'ClassName::methodName'.
A method of an instantiated object can be a callable
   when provided as an array with the object at index 0 and
   the method name at index 1.
The main difference between a Closure object and the
   callable type is that a Closure object is
   scope-independent and can always be invoked, whereas a callable type may be
   scope-dependent and may not be directly invoked.
   Closure is the preferred way to create callables.
While Closure objects are bound to the scope
    where they are created, callables referencing class methods as strings
    or arrays are resolved in the scope where they are called.
    To create a callable from a private or protected method, which can then be
    invoked from outside the class scope, use
    Closure::fromCallable or the
    first-class callable
    syntax.
PHP allows the creation of callables which can be used as a callback argument
   but cannot be called directly.
   These are context-dependent callables which reference a class method in the
   inheritance hierarchy of a class, e.g.
   'parent::method' or ["static", "method"].
As of PHP 8.2.0, context-dependent callables
    are deprecated. Remove the context dependency by replacing
    'parent::method' with
    parent::class . '::method' or use the
    first-class callable
    syntax.
Calling various types of callables with call_user_function
Never
never is a return-only type indicating the function
  does not terminate. This means that it either calls exit,
  throws an exception, or is an infinite loop.
  Therefore, it cannot be part of a
  union type
  declaration. Available as of PHP 8.1.0.
never is, in type theory parlance, the bottom type.
  Meaning it is the subtype of every other type and can replace any other
  return type during inheritance.
Floating point numbers
Floating point numbers (also known as "floats", "doubles", or "real numbers")
  can be specified using any of the following syntaxes:
Formally as of PHP 7.4.0 (previously, underscores have not been allowed):
The size of a float is platform-dependent, although a maximum of approximately 1.8e308
  with a precision of roughly 14 decimal digits is a common value (the 64 bit IEEE
  format).
Floating point precision
Floating point numbers have limited precision. Although it depends on the
   system, PHP typically uses the IEEE 754 double precision format, which will
   give a maximum relative error due to rounding in the order of 1.11e-16.
   Non elementary arithmetic operations may give larger errors, and, of course,
   error propagation must be considered when several operations are
   compounded.
Additionally, rational numbers that are exactly representable as floating
   point numbers in base 10, like 0.1 or
   0.7, do not have an exact representation as floating
   point numbers in base 2, which is used internally, no matter the size of
   the mantissa. Hence, they cannot be converted into their internal binary
   counterparts without a small loss of precision. This can lead to confusing
   results: for example, floor((0.1+0.7)*10) will usually
   return 7 instead of the expected 8,
   since the internal representation will be something like
   7.9999999999999991118....
So never trust floating number results to the last digit, and do not compare
   floating point numbers directly for equality. If higher precision is
   necessary, the arbitrary precision math functions
   and gmp functions are available.
For a "simple" explanation, see the floating point guide
   that's also titled "Why don’t my numbers add up?"
Converting to float
From strings
If the string is
    numeric
    or leading numeric then it will resolve to the
    corresponding float value, otherwise it is converted to zero
    (0).
From other types
For values of other types, the conversion is performed by converting the
    value to int first and then to float. See
    Converting to integer
    for more information.
As certain types have undefined behavior when converting to
     int, this is also the case when converting to
     float.
Comparing floats
As noted in the warning above, testing floating point values for equality is
   problematic, due to the way that they are represented internally. However,
   there are ways to make comparisons of floating point values that work around
   these limitations.
To test floating point values for equality, an upper bound on the relative
   error due to rounding is used. This value is known as the machine epsilon,
   or unit roundoff, and is the smallest acceptable difference in calculations.
$a and $b are equal to 5 digits of
   precision.
Comparing Floats
NaN
Some numeric operations can result in a value represented by the constant
   NAN. This result represents an undefined or
   unrepresentable value in floating-point calculations. Any loose or strict
   comparisons of this value against any other value, including itself, but except , will
   have a result of .
Because NAN represents any number of different values,
   NAN should not be compared to other values, including
   itself, and instead should be checked for using is_nan.
Enumerations
Basic Enumerations
Enumerations are a restricting layer on top of classes and class constants,
   intended to provide a way to define a closed set of possible values for a type.
For a full discussion, see the
   Enumerations chapter.
Casting
If an enum is converted to an object, it is not
   modified. If an enum is converted to an array,
   an array with a single name key (for Pure enums) or
   an array with both name and value keys
   (for Backed enums) is created.  All other cast types will result in an error.
Arrays
For a list of all array functions, see the array functions chapter in the documentation.
An array in PHP is actually an ordered map. A map is a type that
  associates values to keys. This type
  is optimized for several different uses; it can be treated as an array,
  list (vector), hash table (an implementation of a map), dictionary,
  collection, stack, queue, and probably more. As array values can
  be other arrays, trees and multidimensional arrays
  are also possible.
Explanation of those data structures is beyond the scope of this manual, but
  at least one example is provided for each of them. For more information, look
  towards the considerable literature that exists about this broad topic.
Syntax
Specifying with array
An array can be created using the array
    language construct. It takes any number of comma-separated
    key => value pairs
    as arguments.
The comma after the last array element is optional and can be omitted. This is usually done
    for single-line arrays, i.e. array(1, 2) is preferred over
    array(1, 2, ). For multi-line arrays on the other hand the trailing comma
    is commonly used, as it allows easier addition of new elements at the end.
A short array syntax exists which replaces
     array() with [].
A simple array
The key can either be an int
    or a string. The value can be
    of any type.
Additionally the following key casts will occur:
    
     
      
       Strings containing valid decimal ints, unless the number is preceded by a + sign, will be cast to the
       int type. E.g. the key "8" will actually be
       stored under 8. On the other hand "08" will
       not be cast, as it isn't a valid decimal integer.
      
     
     
      
       Floats are also cast to ints, which means that the
       fractional part will be truncated. E.g. the key 8.7 will actually
       be stored under 8.
      
     
     
      
       Bools are cast to ints, too, i.e. the key
        will actually be stored under 1
       and the key  under 0.
      
     
     
      
       Null will be cast to the empty string, i.e. the key
       null will actually be stored under "".
      
     
     
      
       Arrays and objects can not be used as keys.
       Doing so will result in a warning: Illegal offset type.
Strings containing valid decimal ints, unless the number is preceded by a + sign, will be cast to the
       int type. E.g. the key "8" will actually be
       stored under 8. On the other hand "08" will
       not be cast, as it isn't a valid decimal integer.
Floats are also cast to ints, which means that the
       fractional part will be truncated. E.g. the key 8.7 will actually
       be stored under 8.
Bools are cast to ints, too, i.e. the key
        will actually be stored under 1
       and the key  under 0.
Null will be cast to the empty string, i.e. the key
       null will actually be stored under "".
Arrays and objects can not be used as keys.
       Doing so will result in a warning: Illegal offset type.
If multiple elements in the array declaration use the same key, only the last one
    will be used as all others are overwritten.
Type Casting and Overwriting example
As all the keys in the above example are cast to 1, the value will be overwritten
     on every new element and the last assigned value "d" is the only one left over.
PHP arrays can contain int and string keys at the same time
    as PHP does not distinguish between indexed and associative arrays.
Mixed int and string keys
The key is optional. If it is not specified, PHP will
    use the increment of the largest previously used int key.
Indexed arrays without key
It is possible to specify the key only for some elements and leave it out for others:
Keys not on all elements
As you can see the last value "d" was assigned the key
     7. This is because the largest integer key before that
     was 6.
Complex Type Casting and Overwriting example
This example includes all variations of type casting of keys and overwriting
     of elements.
Negative index example
When assigning a negative integer key n, PHP will take care to
     assign the next key to n+1.
Prior to PHP 8.3.0, assigning a negative integer key n would
      assign the next key to 0, the previous example would
      therefore output:
Accessing array elements with square bracket syntax
Array elements can be accessed using the array[key] syntax.
Accessing array elements
Prior to PHP 8.0.0, square brackets and curly braces could be used interchangeably
     for accessing array elements (e.g. $array[42] and $array{42}
     would both do the same thing in the example above).
     The curly brace syntax was deprecated as of PHP 7.4.0 and no longer supported as of PHP 8.0.0.
Array dereferencing
Attempting to access an array key which has not been defined is
      the same as accessing any other undefined variable:
      an E_WARNING-level error message
      (E_NOTICE-level prior to PHP 8.0.0) will be
      issued, and the result will be .
Array dereferencing a scalar value which is not a string
     yields . Prior to PHP 7.4.0, that did not issue an error message.
     As of PHP 7.4.0, this issues E_NOTICE;
     as of PHP 8.0.0, this issues E_WARNING.
Creating/modifying with square bracket syntax
An existing array can be modified by explicitly setting values
    in it.
This is done by assigning values to the array, specifying the
    key in brackets. The key can also be omitted, resulting in an empty pair of
    brackets ([]).
If $arr doesn't exist yet or is set to  or , it will be created, so this is
    also an alternative way to create an array. This practice is
    however discouraged because if $arr already contains
    some value (e.g. string from request variable) then this
    value will stay in the place and [] may actually stand
    for string access
    operator. It is always better to initialize a variable by a direct
    assignment.
As of PHP 7.1.0, applying the empty index operator on a string throws a fatal
     error. Formerly, the string was silently converted to an array.
As of PHP 8.1.0, creating a new array from  value is deprecated.
     Creating a new array from  and undefined values is still allowed.
To change a certain
    value, assign a new value to that element using its key. To remove a
    key/value pair, call the unset function on it.
Using Square Brackets with Arrays
As mentioned above, if no key is specified, the maximum of the existing
     int indices is taken, and the new key will be that maximum
     value plus 1 (but at least 0). If no int indices exist yet, the key will
     be 0 (zero).
Note that the maximum integer key used for this need not
     currently exist in the array. It need only have
     existed in the array at some time since the last time the
     array was re-indexed. The following example illustrates:
Array destructuring
Arrays can be destructured using the [] (as of PHP 7.1.0) or
    list language constructs. These
    constructs can be used to destructure an array into distinct variables.
Array Destructuring
Array destructuring can be used in  to destructure
    a multi-dimensional array while iterating over it.
Array Destructuring in Foreach
Array elements will be ignored if the variable is not provided. Array
    destructuring always starts at index 0.
Ignoring Elements
As of PHP 7.1.0, associative arrays can be destructured too. This also
    allows for easier selection of the right element in numerically indexed
    arrays as the index can be explicitly specified.
Destructuring Associative Arrays
Array destructuring can be used for easy swapping of two variables.
Swapping Two Variable
The spread operator (...) is not supported in assignments.
Attempting to access an array key which has not been defined is
      the same as accessing any other undefined variable:
      an E_WARNING-level error message
      (E_NOTICE-level prior to PHP 8.0.0) will be
      issued, and the result will be .
Destructuring a scalar value assigns  to all variables.
Useful functions
There are quite a few useful functions for working with arrays. See the
   array functions section.
The unset function allows removing keys from an
    array. Be aware that the array will not be
    reindexed. If a true "remove and shift" behavior is desired, the
    array can be reindexed using the
    array_values function.
Unsetting Intermediate Elements
The  control
   structure exists specifically for arrays. It provides an easy
   way to traverse an array.
Array do's and don'ts
Why is $foo[bar] wrong?
Always use quotes around a string literal array index. For example,
    $foo['bar'] is correct, while
    $foo[bar] is not. But why? It is common to encounter this
    kind of syntax in old scripts:
This is wrong, but it works. The reason is that this code has an undefined
    constant (bar) rather than a string ('bar' - notice the
    quotes). It works because PHP automatically converts a
    bare string (an unquoted string which does
    not correspond to any known symbol) into a string which
    contains the bare string. For instance, if there is no defined
    constant named bar, then PHP will substitute in the
    string 'bar' and use that.
The fallback to treat an undefined constant as bare string issues an error
     of level E_NOTICE.
     This has been deprecated as of PHP 7.2.0, and issues an error
     of level E_WARNING.
     As of PHP 8.0.0, it has been removed and throws an
     Error exception.
This does not mean to always quote the key. Do not
    quote keys which are constants or
    variables, as this will prevent
    PHP from interpreting them.
Key Quoting
More examples to demonstrate this behaviour:
More Examples
As stated in the syntax
    section, what's inside the square brackets ('[' and
    ']') must be an expression. This means that code like
    this works:
This is an example of using a function return value as the array index. PHP
    also knows about constants:
Note that E_ERROR is also a valid identifier, just like
    bar in the first example. But the last example is in fact
    the same as writing:
because E_ERROR equals 1, etc.
So why is it bad then?
At some point in the future, the PHP team might want to add another
     constant or keyword, or a constant in other code may interfere. For
     example, it is already wrong to use the words empty and
     default this way, since they are
     reserved keywords.
To reiterate, inside a double-quoted string, it's valid to
      not surround array indexes with quotes so "$foo[bar]"
      is valid. See the above examples for details on why as well as the section
      on variable parsing in
      strings.
Converting to array
For any of the types int, float,
   string, bool and resource,
   converting a value to an array results in an array with a single
   element with index zero and the value of the scalar which was converted. In
   other words, (array) $scalarValue is exactly the same as
   array($scalarValue).
If an object is converted to an array, the result
   is an array whose elements are the object's
   properties. The keys are the member variable names, with a few notable
   exceptions: integer properties are unaccessible;
   private variables have the class name prepended to the variable
   name; protected variables have a '*' prepended to the variable name. These
   prepended values have NUL bytes on either side.
   Uninitialized typed properties
   are silently discarded.
Converting to an Array
These NUL can result in some unexpected behaviour:
Casting an Object to an Array
The above will appear to have two keys named 'AA', although one of them is
   actually named '\0A\0A'.
Converting  to an array results in an empty
   array.
Comparing
It is possible to compare arrays with the array_diff
   function and with
   array operators.
Array unpacking
An array prefixed by ... will be expanded in place during array definition.
   Only arrays and objects which implement Traversable can be expanded.
   Array unpacking with ... is available as of PHP 7.4.0. This is also called
   the spread operator.
It's possible to expand multiple times, and add normal elements before or after the ... operator:

   
    Simple array unpacking
    

<?php
// Using short array syntax.
// Also, works with array() syntax.
$arr1 = [1, 2, 3];
$arr2 = [...$arr1]; // [1, 2, 3]
$arr3 = [0, ...$arr1]; // [0, 1, 2, 3]
$arr4 = [...$arr1, ...$arr2, 111]; // [1, 2, 3, 1, 2, 3, 111]
$arr5 = [...$arr1, ...$arr1]; // [1, 2, 3, 1, 2, 3]

function getArr() {
  return ['a', 'b'];
}
$arr6 = [...getArr(), 'c' => 'd']; // ['a', 'b', 'c' => 'd']

var_dump($arr1, $arr2, $arr3, $arr4, $arr5, $arr6);
?>
Simple array unpacking
Unpacking an array with the ... operator follows the semantics of the array_merge function.
   That is, later string keys overwrite earlier ones and integer keys are renumbered:

   
    Array unpacking with duplicate key
    

<?php
// string key
$arr1 = ["a" => 1];
$arr2 = ["a" => 2];
$arr3 = ["a" => 0, ...$arr1, ...$arr2];
var_dump($arr3); // ["a" => 2]

// integer key
$arr4 = [1, 2, 3];
$arr5 = [4, 5, 6];
$arr6 = [...$arr4, ...$arr5];
var_dump($arr6); // [1, 2, 3, 4, 5, 6]
// Which is [0 => 1, 1 => 2, 2 => 3, 3 => 4, 4 => 5, 5 => 6]
// where the original integer keys have not been retained.
?>
Array unpacking with duplicate key
Keys that are neither integers nor strings throw a TypeError.
    Such keys can only be generated by a Traversable object.
Prior to PHP 8.1, unpacking an array which has a string key is not supported:
Examples
The array type in PHP is very versatile. Here are some examples:
Array Versatility
Using array()
Collection
Changing the values of the array directly is possible
   by passing them by reference.
Changing element in the loop
This example creates a one-based array.
One-based index
Filling an array
Arrays are ordered. The order can be changed using various
   sorting functions. See the array functions
   section for more information. The count function can be
   used to count the number of items in an array.
Sorting an array
Because the value of an array can be anything, it can also be
   another array. This enables the creation of recursive and
   multi-dimensional arrays.
Recursive and multi-dimensional arrays
Array assignment always involves value copying. Use the
   reference operator to copy an
   array by reference.
Array Copying
Type Juggling
PHP does not require explicit type definition in variable declaration.
  In this case, the type of a variable is determined by the value it stores.
  That is to say, if a string is assigned to variable
  $var, then $var is of type
  string. If afterwards an int value is assigned
  to $var, it will be of type int.
PHP may attempt to convert the type of a value to another automatically
  in certain contexts. The different contexts which exist are:
  
   
    Numeric
   
   
    String
   
   
    Logical
   
   
    Integral and string
   
   
    Comparative
   
   
    Function
Numeric
String
Logical
Integral and string
Comparative
Function
When a value needs to be interpreted as a different type, the value itself
   does not change types.
To force a variable to be evaluated as a certain type, see the section on
  Type casting. To change the
  type of a variable, see the settype function.
Numeric contexts
This is the context when using an
   arithmetical operator.
In this context if either operand is a float (or not
   interpretable as an int), both operands are interpreted as
   floats, and the result will be a float.
   Otherwise, the operands will be interpreted as ints,
   and the result will also be an int.
   As of PHP 8.0.0, if one of the operands cannot be interpreted a
   TypeError is thrown.
String contexts
This is the context when using echo,
   print,
   string interpolation,
   or the string
   concatenation operator.
In this context the value will be interpreted as string.
   If the value cannot be interpreted a TypeError is thrown.
   Prior to PHP 7.4.0, an E_RECOVERABLE_ERROR was raised.
Logical contexts
This is the context when using conditional statements, the
   ternary operator,
   or a logical operator.
In this context the value will be interpreted as bool.
Integral and string contexts
This is the context when using
   bitwise operators.
In this context if all operands are of type string the result
   will also be a string.
   Otherwise, the operands will be interpreted as ints,
   and the result will also be an int.
   As of PHP 8.0.0, if one of the operands cannot be interpreted a
   TypeError is thrown.
Comparative contexts
This is the context when using a
   comparison operator.
The type conversions which occur in this context are explained in the
   Comparison with Various Types
   table.
Function contexts
This is the context when a value is passed to a typed parameter, property,
   or returned from a function which declares a return type.
In this context the value must be a value of the type.
   Two exceptions exist, the first one is: if the value is of type
   int and the declared type is float, then the
   integer is converted to a floating point number.
   The second one is: if the declared type is a scalar
   
   type, the value is convertable to a scalar type,
   and the coercive typing mode is active
   (the default), the value may be converted to an accepted scalar value.
   See below for a description of this behaviour.
Internal functions
    automatically coerce  to scalar types,
    this behaviour is DEPRECATED as of PHP 8.1.0.
Coercive typing with simple type declarations
bool type declaration: value is interpreted as bool.
int type declaration: value is interpreted as int
      if the conversion is well-defined. For example the string is
      numeric.
float type declaration: value is interpreted as float
      if the conversion is well-defined. For example the string is
      numeric.
string type declaration: value is interpreted as string.
Coercive typing with union types
When strict_types is not enabled, scalar type declarations
    are subject to limited implicit type coercions.
    If the exact type of the value is not part of the union, then the target type
    is chosen in the following order of preference:

    
     
      
       int
      
     
     
      
       float
      
     
     
      
       string
      
     
     
      
       bool
      
     
    

    If the type exists in the union and the value can be coerced to the
    type under PHP's existing type-checking semantics, then the type is chosen.
    Otherwise, the next type is tried.
int
float
string
bool
As an exception, if the value is a string and both int and float are part
     of the union, the preferred type is determined by the existing
     numeric string
     semantics.
     For example, for "42" int is chosen,
     while for "42.0" float is chosen.
Types that are not part of the above preference list are not eligible
     targets for implicit coercion. In particular no implicit coercions to
     the null, false, and true
     types occur.
Example of types being coerced into a type part of the union
Type Casting
Type casting converts the value to a chosen type by writing the type within
   parentheses before the value to convert.
Type Casting
The casts allowed are:
(integer) is an alias of the (int) cast.
    (boolean) is an alias of the (bool) cast.
    (binary) is an alias of the (string) cast.
    (double) and (real) are aliases of
    the (float) cast.
    These casts do not use the canonical type name and are deprecated as of PHP 8.5.0.
The (real) cast alias has been deprecated as of PHP 7.4.0
    and removed as of PHP 8.0.0.
The (unset) cast has been deprecated as of PHP 7.2.0.
    Note that the (unset) cast is the same as assigning the
    value NULL to the variable or call.
    The (unset) cast is removed as of PHP 8.0.0.
The (binary) cast and b prefix exists
    for forward support. Currently (binary) and
    (string) are identical, however this may change and
    should not be relied upon.
Whitespaces are ignored within the parentheses of a cast.
    Therefore, the following two casts are equivalent:
    
     

<?php
$foo = (int) $bar;
$foo = ( int ) $bar;
?>
Casting literal strings and variables to binary
    strings:
Instead of casting a variable to a string, it is also possible
   to enclose the variable in double quotes.
Different Casting Mechanisms
It may not be obvious exactly what will happen when casting between certain
   types. For more information, see these sections:
   
    Converting to boolean
    Converting to integer
    Converting to float
    Converting to string
    Converting to array
    Converting to object
    Converting to resource
    Converting to NULL
    The type comparison tables
Because PHP supports indexing into strings via offsets
    using the same syntax as array indexing, the following example
    holds true for all PHP versions:
Using Array Offset with a String
See the section titled String
    access by character for more information.
Type declarations
Type declarations can be added to function arguments, return values,
  as of PHP 7.4.0, class properties, and as of PHP 8.3.0, class constants.
  They ensure that the value is of the specified type at call time,
  otherwise a TypeError is thrown.
Every single type that PHP supports, with the exception of
  resource can be used within a user-land type declaration.
  This page contains a changelog of availability of the different types
  and documentation about usage of them in type declarations.
When a class implements an interface method or reimplements a method which
   has already been defined by a parent class, it has to be compatible with the
   aforementioned definition.
   A method is compatible if it follows the
   variance rules.
Atomic Types Usage Notes
Atomic types have straight forward behaviour with some minor caveats which
   are described in this section.
Scalar types
Name aliases for scalar types (bool, int,
     float, string) are not supported.
     Instead, they are treated as class or interface names.
     For example, using boolean as a type declaration
     will require the value to be an  the class or interface
     boolean, rather than of type bool:
void
Returning by reference from a void function is deprecated as of PHP 8.1.0,
     because such a function is contradictory.
     Previously, it already emitted the following
     E_NOTICE when called:
     Only variable references should be returned by reference.
     
      

<?php
function &test(): void {}
?>
Callable types
This type cannot be used as a class property type declaration.
It is not possible to specify the signature of the function.
Type declarations on pass-by-reference Parameters
If a pass-by-reference parameter has a type declaration, the type of the
    variable is only checked on function entry, at the
    beginning of the call, but not when the function returns.
    This means that a function can change the type of variable reference.
Typed pass-by-reference Parameters
Composite Types Usage Notes
Composite type declarations are subject to a couple of restrictions and
   will perform a redundancy check at compile time to prevent simple bugs.
Prior to PHP 8.2.0, and the introduction of DNF types,
    it was not possible to combine intersection types with union types.
Union types
It is not possible to combine the two singleton types false
     and true together in a union type.
     Use bool instead.
Prior to PHP 8.2.0, as false and null
     could not be used as standalone types, a union type comprised of only
     these types was not permitted. This comprises the following types:
     false, false|null,
     and ?false.
Nullable type syntactic sugar
A single base type declaration can be marked nullable by prefixing the
     type with a question mark (?).
     Thus ?T and T|null are identical.
This syntax is supported as of PHP 7.1.0, and predates generalized union
      types support.
It is also possible to achieve nullable arguments by making
      null the default value.
      This is not recommended as if the default value is changed in a child
      class a type compatibility violation will be raised as the
      null type will need to be added to the type declaration.
      This behavior is also deprecated since PHP 8.4.
Old way to make arguments nullable
Duplicate and redundant types
To catch simple bugs in composite type declarations, redundant types that
    can be detected without performing class loading will result in a
    compile-time error. This includes:

    
     
      
       Each name-resolved type may only occur once. Types such as
       int|string|INT or
       CountableTraversableCOUNTABLE
       result in an error.
      
     
     
      
       Using mixed or never results in an error.
      
     
     
      For union types:
      
       
        
         If bool is used, false or true
         cannot be used additionally.
        
       
       
        
         If object is used, class types cannot be used additionally.
        
       
       
        
         If iterable is used, array
         and Traversable cannot be used additionally.
        
       
      
     
     
      For intersection types:
      
       
        
         Using a type which is not a class-type results in an error.
        
       
       
        
         Using either self, parent, or
         static results in an error.
        
       
      
     
     
      For DNF types:
      
       
        
         If a more generic type is used, the more restrictive one is redundant.
        
       
       
        
         Using two identical intersection types.
Each name-resolved type may only occur once. Types such as
       int|string|INT or
       CountableTraversableCOUNTABLE
       result in an error.
Using mixed or never results in an error.
For union types:
If bool is used, false or true
         cannot be used additionally.
If object is used, class types cannot be used additionally.
If iterable is used, array
         and Traversable cannot be used additionally.
For intersection types:
Using a type which is not a class-type results in an error.
Using either self, parent, or
         static results in an error.
For DNF types:
If a more generic type is used, the more restrictive one is redundant.
Using two identical intersection types.
This does not guarantee that the type is “minimal”, because doing so would
     require loading all used class types.
For example, if A and B are class
    aliases, then A|B remains a legal union type, even
    though it could be reduced to either A or
    B.
    Similarly, if class B extends A {}, then A|B
    is also a legal union type, even though it could be reduced to just
    A.

    
     

<?php
function foo(): int|INT {} // Disallowed
function foo(): bool|false {} // Disallowed
function foo(): int&Traversable {} // Disallowed
function foo(): self&Traversable {} // Disallowed

use A as B;
function foo(): A|B {} // Disallowed ("use" is part of name resolution)
function foo(): A&B {} // Disallowed ("use" is part of name resolution)

class_alias('X', 'Y');
function foo(): X|Y {} // Allowed (redundancy is only known at runtime)
function foo(): X&Y {} // Allowed (redundancy is only known at runtime)
?>
Basic class type declaration
Basic interface type declaration
Basic return type declaration
Returning an object
Nullable argument type declaration
Nullable return type declaration
Class property type declaration
Strict typing
By default, PHP will coerce values of the wrong type into the expected
   scalar type declaration if possible. For example, a function that is given
   an int for a parameter that expects a string
   will get a variable of type string.
It is possible to enable strict mode on a per-file basis. In strict
   mode, only a value corresponding exactly to the type declaration will be
   accepted, otherwise a TypeError will be thrown.
   The only exception to this rule is that an int value will
   pass a float type declaration.
Function calls from within internal functions will not be affected by
    the strict_types declaration.
To enable strict mode, the  statement is used with the
   strict_types declaration:
Strict typing applies to function calls made from
    within the file with strict typing enabled, not to
    the functions declared within that file. If a file without strict
    typing enabled makes a call to a function that was defined in a file
    with strict typing, the caller's preference (coercive typing) will be
    respected, and the value will be coerced.
Strict typing is only defined for scalar type declarations.
Strict typing for arguments values
Coercive typing for argument values
Strict typing for return values
Mixed
The mixed type accepts every value. It is equivalent to the
  union type
  
  object|resource|array|string|float|int|bool|null.
  Available as of PHP 8.0.0.
mixed is, in type theory parlance, the top type.
  Meaning every other type is a subtype of it.
Objects
Object Initialization
To create a new object, use the new statement
   to instantiate a class:
Object Construction
For a full discussion, see the
   Classes and Objects chapter.
Converting to object
If an object is converted to an object, it is not
   modified. If a value of any other type is converted to an
   object, a new instance of the stdClass
   built-in class is created. If the value was , the new instance will be
   empty. An array converts to an object with properties
   named by keys and corresponding values. Note that in this case before PHP 7.2.0 numeric keys
   have been inaccessible unless iterated.
Casting to an Object
For any other value, a member variable named scalar will contain
   the value.
(object) cast
NULL
The null type is PHP's unit type, i.e. it has only one value:
  .
Undefined, and unset variables will resolve to the
  value .
Syntax
There is only one value of type null, and that is the
   case-insensitive constant .
Casting to
Casting a variable to null using (unset) $var
   will not remove the variable or unset its value.
   It will only return a  value.
is_null
    unset
Type System
PHP uses a nominal type system with a strong behavioral subtyping relation.
  The subtyping relation is checked at compile time whereas the verification of
  types is dynamically checked at run time.
PHP's type system supports various atomic types that can be composed together
  to create more complex types. Some of these types can be written as
  type declarations.
Atomic types
Some atomic types are built-in types which are tightly integrated with the
   language and cannot be reproduced with user defined types.
The list of base types is:
   
    
     Built-in types
     
      
       
        Scalar types:
       
       
        
         bool type
        
        
         int type
        
        
         float type
        
        
         string type
        
       
      
      
       array type
      
      
       object type
      
      
       resource type
      
      
       never type
      
      
       void type
      
      
       
        Relative class types:
        self, parent, and static
       
      
      
       
        Singleton types
       
       
        
         false
        
        
         true
        
       
      
      
       
        Unit types
       
       
        
         null
        
       
      
     
    
    
     
      User-defined types (generally referred to as class-types)
     
     
      
       Interfaces
      
      
       Classes
      
      
       Enumerations
      
     
    
    
     callable type
Built-in types
Scalar types:
bool type
int type
float type
string type
array type
object type
resource type
never type
void type
Relative class types:
        self, parent, and static
Singleton types
false
true
Unit types
null
User-defined types (generally referred to as class-types)
Interfaces
Classes
Enumerations
callable type
Scalar types
A value is considered scalar if it is of type int,
    float, string or bool.
User-defined types
It is possible to define custom types with
    interfaces,
    classes and
    enumerations.
    These are considered as user-defined types, or class-types.
    For example, a class called Elephant can be defined,
    then objects of type Elephant can be instantiated,
    and a function can request a parameter of type Elephant.
Composite types
It is possible to combine multiple atomic types into composite types.
   PHP allows types to be combined in the following ways:
Intersection of class-types (interfaces and class names).
Union of types.
Intersection types
An intersection type accepts values which satisfies multiple
    class-type declarations, rather than a single one.
    Individual types which form the intersection type are joined by the
    & symbol. Therefore, an intersection type comprised
    of the types T, U, and
    V will be written as T&U&V.
Union types
A union type accepts values of multiple different types,
    rather than a single one.
    Individual types which form the union type are joined by the
    | symbol. Therefore, a union type comprised
    of the types T, U, and
    V will be written as T|U|V.
    If one of the types is an intersection type, it needs to be bracketed
    with parenthesis for it to written in DNF:
    T|(X&Y).
Type aliases
PHP supports two type aliases: mixed and
   iterable which corresponds to the
   union type
   of object|resource|array|string|float|int|bool|null
   and Traversable|array respectively.
PHP does not support user-defined type aliases.
Void
void is a return-only type declaration indicating the
  function does not return a value, but the function may still terminate.
  Therefore, it cannot be part of a
  union type
  declaration. Available as of PHP 7.1.0.
Even if a function has a return type of void it will
   still return a value, this value is always .
Iterables
Iterable is a built-in compile time type alias for
  
  array|Traversable.
  From its introduction in PHP 7.1.0 and prior to PHP 8.2.0,
  iterable was a built-in pseudo-type that acted as the
  aforementioned type alias and can be used as a type declaration.
  An iterable type can be used in  and with
  yield from within a
  generator.
Functions declaring iterable as a return type may also be generators.

   
    
     Iterable generator return type example
    
    
     
<?php

function gen(): iterable {
    yield 1;
    yield 2;
    yield 3;
}

foreach(gen() as $value) {
    echo $value, "\n";
}
?>
Iterable generator return type example
Strings
A string is a series of characters, where a character is
  the same as a byte. This means that PHP only supports a 256-character set,
  and hence does not offer native Unicode support. See
  details of the string
  type.
On 32-bit builds, a string can be as large as up to 2GB
   (2147483647 bytes maximum)
Syntax
A string literal can be specified in four different ways:
single quoted
double quoted
heredoc syntax
nowdoc syntax
Single quoted
The simplest way to specify a string is to enclose it in single
    quotes (the character ').
To specify a literal single quote, escape it with a backslash
    (\). To specify a literal backslash, double it
    (\\). All other instances of backslash will be treated
    as a literal backslash: this means that the other escape sequences you
    might be used to, such as \r or \n,
    will be output literally as specified rather than having any special
    meaning.
Unlike the double-quoted
     and heredoc syntaxes,
     variables and escape sequences
     for special characters will not be expanded when they
     occur in single quoted strings.
Syntax Variants
Double quoted
If the string is enclosed in double-quotes ("), PHP will
    interpret the following escape sequences for special characters:
Escaped characters
As in single quoted strings, escaping any other character will
    result in the backslash being printed too.
The most important feature of double-quoted strings is the fact
    that variable names will be expanded. See
    string interpolation for
    details.
Heredoc
A third way to delimit strings is the heredoc syntax:
    <<<. After this operator, an identifier is
    provided, then a newline. The string itself follows, and then
    the same identifier again to close the quotation.
The closing identifier may be indented by space or tab, in which case
    the indentation will be stripped from all lines in the doc string.
    Prior to PHP 7.3.0, the closing identifier must
    begin in the first column of the line.
Also, the closing identifier must follow the same naming rules as any
    other label in PHP: it must contain only alphanumeric characters and
    underscores, and must start with a non-digit character or underscore.
Basic Heredoc example as of PHP 7.3.0
If the closing identifier is indented further than any lines of the body, then a ParseError will be thrown:
Closing identifier must not be indented further than any lines of the body
If the closing identifier is indented, tabs can be used as well, however,
    tabs and spaces must not be intermixed regarding
    the indentation of the closing identifier and the indentation of the body
     (up to the closing identifier). In any of these cases, a ParseError will be thrown.

    These whitespace constraints have been included because mixing tabs and
    spaces for indentation is harmful to legibility.
Different indentation for body (spaces) closing identifier
The closing identifier for the body string is not required to be
    followed by a semicolon or newline. For example, the following code
    is allowed as of PHP 7.3.0:
Continuing an expression after a closing identifier
If the closing identifier was found at the start of a line, then
     regardless of whether it was a part of another word, it may be considered
     as the closing identifier and causes a ParseError.
Closing identifier in body of the string tends to cause ParseError
To avoid this problem, it is safe to follow the simple rule:
     do not choose a word that appears in the body of the text
     as a closing identifier.
Prior to PHP 7.3.0, it is very important to note that the line with the
     closing identifier must contain no other characters, except a semicolon
     (;).
     That means especially that the identifier
     may not be indented, and there may not be any spaces
     or tabs before or after the semicolon. It's also important to realize that
     the first character before the closing identifier must be a newline as
     defined by the local operating system. This is \n on
     UNIX systems, including macOS. The closing delimiter must also be
     followed by a newline.
If this rule is broken and the closing identifier is not "clean", it will
     not be considered a closing identifier, and PHP will continue looking for
     one. If a proper closing identifier is not found before the end of the
     current file, a parse error will result at the last line.
Invalid example, prior to PHP 7.3.0
Valid example, even prior to PHP 7.3.0
Heredocs containing variables can not be used for initializing class properties.
Heredoc text behaves just like a double-quoted string, without
    the double quotes. This means that quotes in a heredoc do not need to be
    escaped, but the escape codes listed above can still be used. Variables are
    expanded, but the same care must be taken when expressing complex variables
    inside a heredoc as with strings.
Heredoc string quoting example
It is also possible to use the Heredoc syntax to pass data to function
    arguments:
Heredoc in arguments example
It's possible to initialize static variables and class
    properties/constants using the Heredoc syntax:
Using Heredoc to initialize static values
The opening Heredoc identifier may optionally be
    enclosed in double quotes:
Using double quotes in Heredoc
Nowdoc
Nowdocs are to single-quoted strings what heredocs are to double-quoted
    strings. A nowdoc is specified similarly to a heredoc, but no
    String interpolation is done inside a nowdoc. The construct is ideal for
    embedding PHP code or other large blocks of text without the need for
    escaping. It shares some features in common with the SGML
    ![CDATA[ ]] construct, in that it declares a
    block of text which is not for parsing.
A nowdoc is identified with the same 
    sequence used for heredocs, but the identifier which follows is enclosed in
    single quotes, e.g. 'EOT'. All the rules for
    heredoc identifiers also apply to nowdoc identifiers, especially those
    regarding the appearance of the closing identifier.
Nowdoc string quoting example
Nowdoc string quoting example with variables
Static data example
String interpolation
When a string is specified in double quotes or with heredoc,
    variables can be substituted within it.
There are two types of syntax: a
    basic one and an
    advanced one.
    The basic syntax is the most common and convenient. It provides a way to
    embed a variable, an array value, or an object
    property in a string with a minimum of effort.
Basic syntax
If a dollar sign ($) is encountered, the characters
     that follow it which can be used in a variable name will be interpreted
     as such and substituted.
String Interpolation
Formally, the structure for the basic variable substitution syntax is
     as follows:
The ${ expression } syntax is deprecated as of
      PHP 8.2.0, as it can be interpreted as
      variable variables:
      
       

<?php
const foo = 'bar';
$foo = 'foo';
$bar = 'bar';
var_dump("${foo}");
var_dump("${(foo)}");
?>

       
       
       

Deprecated: Using ${var} in strings is deprecated, use {$var} instead in file on line 6

Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in file on line 9
string(3) "foo"
string(3) "bar"

       
       
       

string(3) "foo"
string(3) "bar"

       
      
      The advanced
      string interpolation syntax should be used instead.
If it is not possible to form a valid name the dollar sign remains
      as verbatim in the string:
Interpolating the value of the first dimension of an array or property
The array key must be unquoted, and it is therefore not possible to
      refer to a constant as a key with the basic syntax. Use the
      advanced
      syntax instead.
As of PHP 7.1.0 also negative numeric indices are
     supported.
Negative numeric indices
For anything more complex, the
     advanced
     syntax must be used.
Advanced (curly) syntax
The advanced syntax permits the interpolation of
     variables with arbitrary accessors.
Any scalar variable, array element or object property
     (static or not) with a
     string representation can be included via this syntax.
     The expression is written the same way as it would appear outside the
     string, and then wrapped in { and
     }. Since { can not be escaped, this
     syntax will only be recognised when the $ immediately
     follows the {. Use {\$ to get a
     literal {$. Some examples to make it clear:
Curly Syntax
As this syntax allows arbitrary expressions it is possible to use
      variable variables
      within the advanced syntax.
String access and modification by character
Characters within strings may be accessed and modified by
    specifying the zero-based offset of the desired character after the
    string using square array brackets, as in
    $str[42]. Think of a string as an
    array of characters for this purpose. The functions
    substr and substr_replace
    can be used when you want to extract or replace more than 1 character.
As of PHP 7.1.0, negative string offsets are also supported. These specify
     the offset from the end of the string.
     Formerly, negative offsets emitted E_NOTICE for reading
     (yielding an empty string) and E_WARNING for writing
     (leaving the string untouched).
Prior to PHP 8.0.0, strings could also be accessed using braces, as in
     $str{42}, for the same purpose.
     This curly brace syntax was deprecated as of PHP 7.4.0 and no longer supported as of PHP 8.0.0.
Writing to an out of range offset pads the string with spaces.
     Non-integer types are converted to integer.
     Illegal offset type emits E_WARNING.
     Only the first character of an assigned string is used.
     As of PHP 7.1.0, assigning an empty string throws a fatal error. Formerly,
     it assigned a NULL byte.
Internally, PHP strings are byte arrays. As a result, accessing or
     modifying a string using array brackets is not multi-byte safe, and
     should only be done with strings that are in a single-byte encoding such
     as ISO-8859-1.
As of PHP 7.1.0, applying the empty index operator on an empty string throws a fatal
     error. Formerly, the empty string was silently converted to an array.
Some string examples
String offsets have to either be integers or integer-like strings,
    otherwise a warning will be thrown.
Example of Illegal String Offsets
Accessing variables of other types (not including arrays or objects
     implementing the appropriate interfaces) using [] or
     {} silently returns .
Characters within string literals can be accessed
     using [] or {}.
Accessing characters within string literals using the
     {} syntax has been deprecated in PHP 7.4.
     This has been removed in PHP 8.0.
Useful functions and operators
Strings may be concatenated using the '.' (dot) operator. Note
   that the '+' (addition) operator will not work for this.
   See String operators for
   more information.
There are a number of useful functions for string manipulation.
See the string functions section for
   general functions, and the Perl-compatible regular
   expression functions for advanced find  replace functionality.
There are also functions for URL strings, and
   functions to encrypt/decrypt strings
   (Sodium and
   Hash).
Finally, see also the character type
   functions.
Converting to string
A value can be converted to a string using the
   (string) cast or the strval function.
   String conversion is automatically done in the scope of an
   expression where a string is needed. This happens when using the
   echo or print functions, or when a
   variable is compared to a string. The sections on
   Types and
   Type Juggling will make
   the following clearer. See also the settype function.
A bool  value is converted to the string
   "1". bool  is converted to
   "" (the empty string). This allows conversion back and
   forth between bool and string values.
An int or float is converted to a
   string representing the number textually (including the
   exponent part for floats). Floating point numbers can be
   converted using exponential notation (4.1E+6).
As of PHP 8.0.0, the decimal point character is always
    a period ("."). Prior to PHP 8.0.0,
    the decimal point character is defined in the script's locale (category
    LC_NUMERIC). See the setlocale function.
Arrays are always converted to the string
   "Array"; because of this, echo and
   print can not by themselves show the contents of an
   array. To view a single element, use a construction such as
   echo $arr['foo']. See below for tips on viewing the entire
   contents.
In order to convert objects to string, the magic
   method __toString must be used.
Resources are always converted to strings with the
   structure "Resource id #1", where 1
   is the resource number assigned to the resource by PHP at
   runtime. While the exact structure of this string should not be relied on
   and is subject to change, it will always be unique for a given resource
   within the lifetime of a script being executed (ie a Web request or CLI
   process) and won't be reused. To get a resource's type, use
   the get_resource_type function.
is always converted to an empty string.
As stated above, directly converting an array,
   object, or resource to a string does
   not provide any useful information about the value beyond its type. See the
   functions print_r and var_dump for
   more effective means of inspecting the contents of these types.
Most PHP values can also be converted to strings for permanent
   storage. This method is called serialization, and is performed by the
   serialize function.
Details of the String Type
The string in PHP is implemented as an array of bytes and an
   integer indicating the length of the buffer. It has no information about how
   those bytes translate to characters, leaving that task to the programmer.
   There are no limitations on the values the string can be composed of; in
   particular, bytes with value 0 (“NUL bytes”) are allowed
   anywhere in the string (however, a few functions, said in this manual not to
   be “binary safe”, may hand off the strings to libraries that ignore data
   after a NUL byte.)
This nature of the string type explains why there is no separate “byte” type
   in PHP – strings take this role. Functions that return no textual data – for
   instance, arbitrary data read from a network socket – will still return
   strings.
Given that PHP does not dictate a specific encoding for strings, one might
   wonder how string literals are encoded. For instance, is the string
   "á" equivalent to "\xE1" (ISO-8859-1),
   "\xC3\xA1" (UTF-8, C form),
   "\x61\xCC\x81" (UTF-8, D form) or any other possible
   representation? The answer is that string will be encoded in whatever fashion
   it is encoded in the script file. Thus, if the script is written in
   ISO-8859-1, the string will be encoded in ISO-8859-1 and so on. However,
   this does not apply if Zend Multibyte is enabled; in that case, the script
   may be written in an arbitrary encoding (which is explicitly declared or is
   detected) and then converted to a certain internal encoding, which is then
   the encoding that will be used for the string literals.
   Note that there are some constraints on the encoding of the script (or on the
   internal encoding, should Zend Multibyte be enabled) – this almost always
   means that this encoding should be a compatible superset of ASCII, such as
   UTF-8 or ISO-8859-1. Note, however, that state-dependent encodings where
   the same byte values can be used in initial and non-initial shift states
   may be problematic.
Of course, in order to be useful, functions that operate on text may have to
   make some assumptions about how the string is encoded. Unfortunately, there
   is much variation on this matter throughout PHP’s functions:
Some functions assume that the string is encoded in some (any) single-byte
     encoding, but they do not need to interpret those bytes as specific
     characters. This is case of, for instance, substr,
     strpos, strlen or
     strcmp. Another way to think of these functions is
     that operate on memory buffers, i.e., they work with bytes and byte
     offsets.
Other functions are passed the encoding of the string, possibly they also
     assume a default if no such information is given. This is the case of
     htmlentities and the majority of the
     functions in the mbstring extension.
Others use the current locale (see setlocale), but
     operate byte-by-byte.
Finally, they may just assume the string is using a specific encoding,
     usually UTF-8. This is the case of most functions in the
     intl extension and in the
     PCRE extension
     (in the last case, only when the u modifier is used).
Ultimately, this means writing correct programs using Unicode depends on
   carefully avoiding functions that will not work and that most likely will
   corrupt the data and using instead the functions that do behave correctly,
   generally from the intl and
   mbstring extensions.
   However, using functions that can handle Unicode encodings is just the
   beginning. No matter the functions the language provides, it is essential to
   know the Unicode specification. For instance, a program that assumes there is
   only uppercase and lowercase is making a wrong assumption.
Singleton types
Singleton types are those which allow only one value.
  PHP has support for two singleton types:
  false as of PHP 8.0.0 and true
  as of PHP 8.2.0.
Prior to PHP 8.2.0 the false type
   could only be used as part of a
   union type.
It is not possible to define custom singleton types. Consider using an
   enumerations instead.
Relative class types
These types declarations can only be used within classes.
self
The value must be an  the same class as the one
   in which the type declaration is used.
parent
The value must be an  a parent of the class
   in which the type declaration is used.
static
static is a return-only type which requires that the
   value returned must be an  the same class as the one
   the method is called in.
   Available as of PHP 8.0.0.
Resources
A resource is a special variable, holding a reference to an
  external resource. Resources are created and used by special functions. See
  the appendix for a listing of all these
  functions and the corresponding resource types.
See also the get_resource_type function.
Converting to resource
As resource variables hold special handles to opened files,
   database connections, image canvas areas and the like, converting to a
   resource makes no sense.
Freeing resources
Thanks to the reference-counting system being part of Zend Engine,
   a resource with no more references to it is detected
   automatically, and it is freed by the garbage collector. For this reason, it
   is rarely necessary to free the memory manually.
Persistent database links are an exception to this rule. They are
    not destroyed by the garbage collector. See the
    persistent
    connections section for more information.
Bitwise Operators
Bitwise operators allow evaluation and manipulation of specific
  bits within an integer.
Bitwise Operators
Bit shifting in PHP is arithmetic.
  Bits shifted off either end are discarded.
  Left shifts have zeros shifted in on the right while the sign
  bit is shifted out on the left, meaning the sign of an operand
  is not preserved.
  Right shifts have copies of the sign bit shifted in on the left,
  meaning the sign of an operand is preserved.
Use parentheses to ensure the desired
  precedence.
  For example, $a & $b == true evaluates
  the equivalency then the bitwise and; while
  ($a & $b) == true evaluates the bitwise and
  then the equivalency.
If both operands for the &, | and
  ^ operators are strings, then the operation will be
  performed on the ASCII values of the characters that make up the strings and
  the result will be a string. In all other cases, both operands will be
  converted to integers
  and the result will be an integer.
If the operand for the ~ operator is a string, the
  operation will be performed on the ASCII values of the characters that make
  up the string and the result will be a string, otherwise the operand and the
  result will be treated as integers.
Both operands and the result for the << and
  >> operators are always treated as integers.
PHP's error_reporting ini setting uses bitwise values,
  providing a real-world demonstration of turning
  bits off. To show all errors, except for notices,
  the php.ini file instructions say to use:
  E_ALL & ~E_NOTICE
This works by starting with E_ALL:
     00000000000000000111011111111111
     Then taking the value of E_NOTICE...
     00000000000000000000000000001000
     ... and inverting it via ~:
     11111111111111111111111111110111
     Finally, it uses AND (&) to find the bits turned
     on in both values:
     00000000000000000111011111110111
This works by starting with E_ALL:
     00000000000000000111011111111111
     Then taking the value of E_NOTICE...
     00000000000000000000000000001000
     ... and inverting it via ~:
     11111111111111111111111111110111
     Finally, it uses AND (&) to find the bits turned
     on in both values:
     00000000000000000111011111110111
Another way to accomplish that is using XOR (^) to find
  bits that are on in only one value or the other: E_ALL ^
  E_NOTICE
error_reporting can also be used to demonstrate turning bits on.
  The way to show just errors and recoverable errors is:
  E_ERROR | E_RECOVERABLE_ERROR
This process combines E_ERROR
     00000000000000000000000000000001
     and
     00000000000000000001000000000000
     using the OR (|) operator
     to get the bits turned on in either value:
     00000000000000000001000000000001
This process combines E_ERROR
     00000000000000000000000000000001
     and
     00000000000000000001000000000000
     using the OR (|) operator
     to get the bits turned on in either value:
     00000000000000000001000000000001
Bitwise AND, OR and XOR operations on integers
   

<?php
/*
 * Ignore the top section,
 * it is just formatting to make output clearer.
 */

$format = '(%1$2d = %1$04b) = (%2$2d = %2$04b)'
        . ' %3$s (%4$2d = %4$04b)' . "\n";

echo <<<EOH
 ---------     ---------  -- ---------
 result        value      op test
 ---------     ---------  -- ---------
EOH;


/*
 * Here are the examples.
 */

$values = array(0, 1, 2, 4, 8);
$test = 1 + 4;

echo "\n Bitwise AND \n";
foreach ($values as $value) {
    $result = $value & $test;
    printf($format, $result, $value, '&', $test);
}

echo "\n Bitwise Inclusive OR \n";
foreach ($values as $value) {
    $result = $value | $test;
    printf($format, $result, $value, '|', $test);
}

echo "\n Bitwise Exclusive OR (XOR) \n";
foreach ($values as $value) {
    $result = $value ^ $test;
    printf($format, $result, $value, '^', $test);
}
?>

   
   
   

 ---------     ---------  -- ---------
 result        value      op test
 ---------     ---------  -- ---------
 Bitwise AND
( 0 = 0000) = ( 0 = 0000) & ( 5 = 0101)
( 1 = 0001) = ( 1 = 0001) & ( 5 = 0101)
( 0 = 0000) = ( 2 = 0010) & ( 5 = 0101)
( 4 = 0100) = ( 4 = 0100) & ( 5 = 0101)
( 0 = 0000) = ( 8 = 1000) & ( 5 = 0101)

 Bitwise Inclusive OR
( 5 = 0101) = ( 0 = 0000) | ( 5 = 0101)
( 5 = 0101) = ( 1 = 0001) | ( 5 = 0101)
( 7 = 0111) = ( 2 = 0010) | ( 5 = 0101)
( 5 = 0101) = ( 4 = 0100) | ( 5 = 0101)
(13 = 1101) = ( 8 = 1000) | ( 5 = 0101)

 Bitwise Exclusive OR (XOR)
( 5 = 0101) = ( 0 = 0000) ^ ( 5 = 0101)
( 4 = 0100) = ( 1 = 0001) ^ ( 5 = 0101)
( 7 = 0111) = ( 2 = 0010) ^ ( 5 = 0101)
( 1 = 0001) = ( 4 = 0100) ^ ( 5 = 0101)
(13 = 1101) = ( 8 = 1000) ^ ( 5 = 0101)
Bitwise AND, OR and XOR operations on integers
Bitwise XOR operations on strings
   

<?php
echo 12 ^ 9, PHP_EOL; // Outputs '5'

echo "12" ^ "9", PHP_EOL; // Outputs the Backspace character (ascii 8)
                          // ('1' (ascii 49)) ^ ('9' (ascii 57)) = #8

echo "hallo" ^ "hello", PHP_EOL; // Outputs the ascii values #0 #4 #0 #0 #0
                                 // 'a' ^ 'e' = #4

echo 2 ^ "3", PHP_EOL; // Outputs 1
                       // 2 ^ ((int) "3") == 1

echo "2" ^ 3, PHP_EOL; // Outputs 1
                       // ((int) "2") ^ 3 == 1
?>
Bitwise XOR operations on strings
Bit shifting on integers
   

<?php
/*
 * Here are the examples.
 */

echo "\n--- BIT SHIFT RIGHT ON POSITIVE INTEGERS ---\n";

$val = 4;
$places = 1;
$res = $val >> $places;
p($res, $val, '>>', $places, 'copy of sign bit shifted into left side');

$val = 4;
$places = 2;
$res = $val >> $places;
p($res, $val, '>>', $places);

$val = 4;
$places = 3;
$res = $val >> $places;
p($res, $val, '>>', $places, 'bits shift out right side');

$val = 4;
$places = 4;
$res = $val >> $places;
p($res, $val, '>>', $places, 'same result as above; can not shift beyond 0');


echo "\n--- BIT SHIFT RIGHT ON NEGATIVE INTEGERS ---\n";

$val = -4;
$places = 1;
$res = $val >> $places;
p($res, $val, '>>', $places, 'copy of sign bit shifted into left side');

$val = -4;
$places = 2;
$res = $val >> $places;
p($res, $val, '>>', $places, 'bits shift out right side');

$val = -4;
$places = 3;
$res = $val >> $places;
p($res, $val, '>>', $places, 'same result as above; can not shift beyond -1');


echo "\n--- BIT SHIFT LEFT ON POSITIVE INTEGERS ---\n";

$val = 4;
$places = 1;
$res = $val << $places;
p($res, $val, '<<', $places, 'zeros fill in right side');

$val = 4;
$places = (PHP_INT_SIZE * 8) - 4;
$res = $val << $places;
p($res, $val, '<<', $places);

$val = 4;
$places = (PHP_INT_SIZE * 8) - 3;
$res = $val << $places;
p($res, $val, '<<', $places, 'sign bits get shifted out');

$val = 4;
$places = (PHP_INT_SIZE * 8) - 2;
$res = $val << $places;
p($res, $val, '<<', $places, 'bits shift out left side');


echo "\n--- BIT SHIFT LEFT ON NEGATIVE INTEGERS ---\n";

$val = -4;
$places = 1;
$res = $val << $places;
p($res, $val, '<<', $places, 'zeros fill in right side');

$val = -4;
$places = (PHP_INT_SIZE * 8) - 3;
$res = $val << $places;
p($res, $val, '<<', $places);

$val = -4;
$places = (PHP_INT_SIZE * 8) - 2;
$res = $val << $places;
p($res, $val, '<<', $places, 'bits shift out left side, including sign bit');


/*
 * Ignore this bottom section,
 * it is just formatting to make output clearer.
 */

function p($res, $val, $op, $places, $note = '') {
    $format = '%0' . (PHP_INT_SIZE * 8) . "b\n";

    printf("Expression: %d = %d %s %d\n", $res, $val, $op, $places);

    echo " Decimal:\n";
    printf("  val=%d\n", $val);
    printf("  res=%d\n", $res);

    echo " Binary:\n";
    printf('  val=' . $format, $val);
    printf('  res=' . $format, $res);

    if ($note) {
        echo " NOTE: $note\n";
    }

    echo "\n\n";
}
?>

   
   
   


--- BIT SHIFT RIGHT ON POSITIVE INTEGERS ---
Expression: 2 = 4 >> 1
 Decimal:
  val=4
  res=2
 Binary:
  val=00000000000000000000000000000100
  res=00000000000000000000000000000010
 NOTE: copy of sign bit shifted into left side

Expression: 1 = 4 >> 2
 Decimal:
  val=4
  res=1
 Binary:
  val=00000000000000000000000000000100
  res=00000000000000000000000000000001

Expression: 0 = 4 >> 3
 Decimal:
  val=4
  res=0
 Binary:
  val=00000000000000000000000000000100
  res=00000000000000000000000000000000
 NOTE: bits shift out right side

Expression: 0 = 4 >> 4
 Decimal:
  val=4
  res=0
 Binary:
  val=00000000000000000000000000000100
  res=00000000000000000000000000000000
 NOTE: same result as above; can not shift beyond 0


--- BIT SHIFT RIGHT ON NEGATIVE INTEGERS ---
Expression: -2 = -4 >> 1
 Decimal:
  val=-4
  res=-2
 Binary:
  val=11111111111111111111111111111100
  res=11111111111111111111111111111110
 NOTE: copy of sign bit shifted into left side

Expression: -1 = -4 >> 2
 Decimal:
  val=-4
  res=-1
 Binary:
  val=11111111111111111111111111111100
  res=11111111111111111111111111111111
 NOTE: bits shift out right side

Expression: -1 = -4 >> 3
 Decimal:
  val=-4
  res=-1
 Binary:
  val=11111111111111111111111111111100
  res=11111111111111111111111111111111
 NOTE: same result as above; can not shift beyond -1


--- BIT SHIFT LEFT ON POSITIVE INTEGERS ---
Expression: 8 = 4 << 1
 Decimal:
  val=4
  res=8
 Binary:
  val=00000000000000000000000000000100
  res=00000000000000000000000000001000
 NOTE: zeros fill in right side

Expression: 1073741824 = 4 << 28
 Decimal:
  val=4
  res=1073741824
 Binary:
  val=00000000000000000000000000000100
  res=01000000000000000000000000000000

Expression: -2147483648 = 4 << 29
 Decimal:
  val=4
  res=-2147483648
 Binary:
  val=00000000000000000000000000000100
  res=10000000000000000000000000000000
 NOTE: sign bits get shifted out

Expression: 0 = 4 << 30
 Decimal:
  val=4
  res=0
 Binary:
  val=00000000000000000000000000000100
  res=00000000000000000000000000000000
 NOTE: bits shift out left side


--- BIT SHIFT LEFT ON NEGATIVE INTEGERS ---
Expression: -8 = -4 << 1
 Decimal:
  val=-4
  res=-8
 Binary:
  val=11111111111111111111111111111100
  res=11111111111111111111111111111000
 NOTE: zeros fill in right side

Expression: -2147483648 = -4 << 29
 Decimal:
  val=-4
  res=-2147483648
 Binary:
  val=11111111111111111111111111111100
  res=10000000000000000000000000000000

Expression: 0 = -4 << 30
 Decimal:
  val=-4
  res=0
 Binary:
  val=11111111111111111111111111111100
  res=00000000000000000000000000000000
 NOTE: bits shift out left side, including sign bit

   
   
   


--- BIT SHIFT RIGHT ON POSITIVE INTEGERS ---
Expression: 2 = 4 >> 1
 Decimal:
  val=4
  res=2
 Binary:
  val=0000000000000000000000000000000000000000000000000000000000000100
  res=0000000000000000000000000000000000000000000000000000000000000010
 NOTE: copy of sign bit shifted into left side

Expression: 1 = 4 >> 2
 Decimal:
  val=4
  res=1
 Binary:
  val=0000000000000000000000000000000000000000000000000000000000000100
  res=0000000000000000000000000000000000000000000000000000000000000001

Expression: 0 = 4 >> 3
 Decimal:
  val=4
  res=0
 Binary:
  val=0000000000000000000000000000000000000000000000000000000000000100
  res=0000000000000000000000000000000000000000000000000000000000000000
 NOTE: bits shift out right side

Expression: 0 = 4 >> 4
 Decimal:
  val=4
  res=0
 Binary:
  val=0000000000000000000000000000000000000000000000000000000000000100
  res=0000000000000000000000000000000000000000000000000000000000000000
 NOTE: same result as above; can not shift beyond 0


--- BIT SHIFT RIGHT ON NEGATIVE INTEGERS ---
Expression: -2 = -4 >> 1
 Decimal:
  val=-4
  res=-2
 Binary:
  val=1111111111111111111111111111111111111111111111111111111111111100
  res=1111111111111111111111111111111111111111111111111111111111111110
 NOTE: copy of sign bit shifted into left side

Expression: -1 = -4 >> 2
 Decimal:
  val=-4
  res=-1
 Binary:
  val=1111111111111111111111111111111111111111111111111111111111111100
  res=1111111111111111111111111111111111111111111111111111111111111111
 NOTE: bits shift out right side

Expression: -1 = -4 >> 3
 Decimal:
  val=-4
  res=-1
 Binary:
  val=1111111111111111111111111111111111111111111111111111111111111100
  res=1111111111111111111111111111111111111111111111111111111111111111
 NOTE: same result as above; can not shift beyond -1


--- BIT SHIFT LEFT ON POSITIVE INTEGERS ---
Expression: 8 = 4 << 1
 Decimal:
  val=4
  res=8
 Binary:
  val=0000000000000000000000000000000000000000000000000000000000000100
  res=0000000000000000000000000000000000000000000000000000000000001000
 NOTE: zeros fill in right side

Expression: 4611686018427387904 = 4 << 60
 Decimal:
  val=4
  res=4611686018427387904
 Binary:
  val=0000000000000000000000000000000000000000000000000000000000000100
  res=0100000000000000000000000000000000000000000000000000000000000000

Expression: -9223372036854775808 = 4 << 61
 Decimal:
  val=4
  res=-9223372036854775808
 Binary:
  val=0000000000000000000000000000000000000000000000000000000000000100
  res=1000000000000000000000000000000000000000000000000000000000000000
 NOTE: sign bits get shifted out

Expression: 0 = 4 << 62
 Decimal:
  val=4
  res=0
 Binary:
  val=0000000000000000000000000000000000000000000000000000000000000100
  res=0000000000000000000000000000000000000000000000000000000000000000
 NOTE: bits shift out left side


--- BIT SHIFT LEFT ON NEGATIVE INTEGERS ---
Expression: -8 = -4 << 1
 Decimal:
  val=-4
  res=-8
 Binary:
  val=1111111111111111111111111111111111111111111111111111111111111100
  res=1111111111111111111111111111111111111111111111111111111111111000
 NOTE: zeros fill in right side

Expression: -9223372036854775808 = -4 << 61
 Decimal:
  val=-4
  res=-9223372036854775808
 Binary:
  val=1111111111111111111111111111111111111111111111111111111111111100
  res=1000000000000000000000000000000000000000000000000000000000000000

Expression: 0 = -4 << 62
 Decimal:
  val=-4
  res=0
 Binary:
  val=1111111111111111111111111111111111111111111111111111111111111100
  res=0000000000000000000000000000000000000000000000000000000000000000
 NOTE: bits shift out left side, including sign bit
Bit shifting on integers
Use functions from the gmp extension for
   bitwise manipulation on numbers beyond PHP_INT_MAX.
pack
    unpack
    gmp_and
    gmp_or
    gmp_xor
    gmp_testbit
    gmp_clrbit
Type Operators
instanceof is used to determine whether a PHP variable
  is an instantiated object of a certain
  class:
  
   Using instanceof with classes
   

<?php
class MyClass
{
}

class NotMyClass
{
}
$a = new MyClass;

var_dump($a instanceof MyClass);
var_dump($a instanceof NotMyClass);
?>

   
   
   

bool(true)
bool(false)
Using instanceof with classes
instanceof can also be used to determine whether a variable
  is an instantiated object of a class that inherits from a parent class:
  
   Using instanceof with inherited classes
   

<?php
class ParentClass
{
}

class MyClass extends ParentClass
{
}

$a = new MyClass;

var_dump($a instanceof MyClass);
var_dump($a instanceof ParentClass);
?>

   
   
   

bool(true)
bool(true)
Using instanceof with inherited classes
To check if an object is not an instanceof a class, the
  logical not
   operator can be used.
  
   Using instanceof to check if object is not an
    instanceof a class
   

<?php
class MyClass
{
}

$a = new MyClass;
var_dump(!($a instanceof stdClass));
?>

   
   
   

bool(true)
Using instanceof to check if object is not an
    instanceof a class
Lastly, instanceof can also be used to determine whether
  a variable is an instantiated object of a class that implements an
  interface:
  
   Using instanceof with interfaces
   

<?php
interface MyInterface
{
}

class MyClass implements MyInterface
{
}

$a = new MyClass;

var_dump($a instanceof MyClass);
var_dump($a instanceof MyInterface);
?>

   
   
   

bool(true)
bool(true)
Using instanceof with interfaces
Although instanceof is usually used with a literal classname,
  it can also be used with another object or a string variable:
  
   Using instanceof with other variables
   

<?php
interface MyInterface
{
}

class MyClass implements MyInterface
{
}

$a = new MyClass;
$b = new MyClass;
$c = 'MyClass';
$d = 'NotMyClass';

var_dump($a instanceof $b); // $b is an object of class MyClass
var_dump($a instanceof $c); // $c is a string 'MyClass'
var_dump($a instanceof $d); // $d is a string 'NotMyClass'
?>

   
   
   

bool(true)
bool(true)
bool(false)
Using instanceof with other variables
instanceof does not throw any error if the variable being tested is not
  an object, it simply returns . Constants, however, were not allowed
  prior to PHP 7.3.0.
  
   Using instanceof to test other variables
   

<?php
$a = 1;
$b = NULL;
$c = fopen('/tmp/', 'r');
var_dump($a instanceof stdClass); // $a is an integer
var_dump($b instanceof stdClass); // $b is NULL
var_dump($c instanceof stdClass); // $c is a resource
var_dump(FALSE instanceof stdClass);
?>

   
   
   

bool(false)
bool(false)
bool(false)
PHP Fatal error:  instanceof expects an object instance, constant given
Using instanceof to test other variables
As of PHP 7.3.0, constants are allowed on the left-hand-side of the
  instanceof operator.
  
   Using instanceof to test constants
   

<?php
var_dump(FALSE instanceof stdClass);
?>

   
   
   

bool(false)
Using instanceof to test constants
As of PHP 8.0.0, instanceof can now be used with arbitrary expressions.
  The expression must be wrapped in parentheses and produce a string.
  
  
   Using instanceof with an arbitrary expression
   

<?php

class ClassA extends \stdClass {}
class ClassB extends \stdClass {}
class ClassC extends ClassB {}
class ClassD extends ClassA {}

function getSomeClass(): string
{
    return ClassA::class;
}

var_dump(new ClassA instanceof ('std' . 'Class'));
var_dump(new ClassB instanceof ('Class' . 'B'));
var_dump(new ClassC instanceof ('Class' . 'A'));
var_dump(new ClassD instanceof (getSomeClass()));
?>

   
   
   

bool(true)
bool(true)
bool(false)
bool(true)
Using instanceof with an arbitrary expression
The instanceof operator has a functional variant
  with the is_a function.
get_class
    is_a
Logical Operators
Logical Operators
The reason for the two different variations of "and" and "or"
  operators is that they operate at different precedences. (See
  Operator
   Precedence.)
Logical operators illustrated
Arithmetic Operators
Remember basic arithmetic from school? These work just
  like those.
Arithmetic Operators
The division operator / returns a float
  value unless the two operands are int (or
  numeric strings
  which are type juggled to int) and the numerator is a multiple
  of the divisor, in which case an integer value will be returned.
  For integer division, see intdiv.
Operands of modulo are converted to int
  before processing. For floating-point modulo, see
  fmod.
The result of the modulo operator % has the same sign
  as the dividend — that is, the result of $a % $b
  will have the same sign as $a. For example:
  
   The Modulo Operator
   

<?php
var_dump(5 % 3);
var_dump(5 % -3);
var_dump(-5 % 3);
var_dump(-5 % -3);
?>

   
   
   

int(2)
int(2)
int(-2)
int(-2)
The Modulo Operator
Math functions
Array Operators
Array Operators
The + operator returns the right-hand array appended
  to the left-hand array; for keys that exist in both arrays, the elements
  from the left-hand array will be used, and the matching elements from the
  right-hand array will be ignored.
Array Append Operator
   

<?php
$a = array("a" => "apple", "b" => "banana");
$b = array("a" => "pear", "b" => "strawberry", "c" => "cherry");

$c = $a + $b; // Union of $a and $b
echo "Union of \$a and \$b: \n";
var_dump($c);

$c = $b + $a; // Union of $b and $a
echo "Union of \$b and \$a: \n";
var_dump($c);

$a += $b; // Union of $a += $b is $a and $b
echo "Union of \$a += \$b: \n";
var_dump($a);
?>

   
   
   

Union of $a and $b:
array(3) {
  ["a"]=>
  string(5) "apple"
  ["b"]=>
  string(6) "banana"
  ["c"]=>
  string(6) "cherry"
}
Union of $b and $a:
array(3) {
  ["a"]=>
  string(4) "pear"
  ["b"]=>
  string(10) "strawberry"
  ["c"]=>
  string(6) "cherry"
}
Union of $a += $b:
array(3) {
  ["a"]=>
  string(5) "apple"
  ["b"]=>
  string(6) "banana"
  ["c"]=>
  string(6) "cherry"
}
Array Append Operator
Elements of arrays are equal for the comparison if they have the
  same key and value.
Comparing arrays
   

<?php
$a = array("apple", "banana");
$b = array(1 => "banana", "0" => "apple");

var_dump($a == $b); // bool(true)
var_dump($a === $b); // bool(false)
?>
Comparing arrays
Array type
    Array functions
Execution Operators
PHP supports one execution operator: backticks (``). Note that
  these are not single-quotes! PHP will attempt to execute the
  contents of the backticks as a shell command; the output will be
  returned (i.e., it won't simply be dumped to output; it can be
  assigned to a variable).  Use of the backtick operator is identical
  to shell_exec.
Backtick Operator
   

<?php
$output = `ls -al`;
echo "<pre>$output</pre>";
?>
Backtick Operator
The backtick operator is disabled when
   shell_exec is disabled.
Unlike some other languages, backticks have no special meaning
   within double-quoted strings.
Program Execution functions
    popen
    proc_open
    Using PHP from the commandline
Functional Operators
PHP 8.5 and later supports one operator that works directly on callables.  The |>
  operator, or “pipe,” accepts a single-parameter callable on the right and passes
  the left-side value to it, evaluating to the callable's result.  The callable
  on the right may be any valid PHP callable: a Closure,
  a first-class callable,
  an object that implements __invoke(), etc.
That means the following two lines are logically equivalent.
  
   Using |>
   

<?php
$result = "Hello World" |> strlen(...);
echo $result, PHP_EOL;

$result = strlen("Hello World");
echo $result, PHP_EOL;
?>

   
   
   

11
11
Using |>
For a single call that is not especially useful. It becomes useful when multiple calls are chained together.
  That is, the following two code fragments are logically equivalent:
  
   Chaining | calls
   

<?php
$result = "PHP Rocks"
    |> htmlentities(...)
    |> str_split(...)
    |> (fn($x) => array_map(strtoupper(...), $x))
    |> (fn($x) => array_filter($x, fn($v) => $v != 'O'))
;
print_r($result);

$temp = "PHP Rocks";
$temp = htmlentities($temp);
$temp = str_split($temp);
$temp = array_map(strtoupper(...), $temp);
$temp = array_filter($temp, fn($v) => $v != 'O');
$result = $temp;
print_r($result);
?>

   
   
   

Array
(
    [0] => P
    [1] => H
    [2] => P
    [3] =>
    [4] => R
    [6] => C
    [7] => K
    [8] => S
)
Array
(
    [0] => P
    [1] => H
    [2] => P
    [3] =>
    [4] => R
    [6] => C
    [7] => K
    [8] => S
)
Chaining | calls
The left-hand side of the pipe may be any value or expression.  The right-hand side
  may be any valid PHP callable that takes a single parameter, or any expression
  that evaluates to such a callable.  Functions with more than one required parameter
  are not allowed and will fail as if the function were called normally
  with insufficient arguments. Functions that take a variable by reference are not allowed.
  If the right-hand side does not evaluate to a valid callable it will throw an Error.
Be aware that, to avoid syntax ambiguity, arrow functions
   MUST be wrapped in parentheses when used with a pipe operator, as in the examples above.
   Failing to do so will result in a fatal error.
Closure
Comparison Operators
Comparison operators, as their name implies, allow you to compare
  two values.  You may also be interested in viewing
  the type comparison tables,
  as they show examples of various type related comparisons.
Comparison Operators
If both operands are
  numeric strings,
  or one operand is a number and the other one is a
  numeric string,
  then the comparison is done numerically.
  These rules also apply to the
  switch statement.
  The type conversion does not take place when the comparison is
  === or !== as this involves
  comparing the type as well as the value.
Prior to PHP 8.0.0, if a string is compared to a number
   or a numeric string then the string was converted to a
   number before performing the comparison. This can lead to surprising
   results as can be seen with the following example:
   
    

<?php
var_dump(0 == "a");
var_dump("1" == "01");
var_dump("10" == "1e1");
var_dump(100 == "1e2");

switch ("a") {
case 0:
    echo "0";
    break;
case "a":
    echo "a";
    break;
}
?>

    
    
    

bool(true)
bool(true)
bool(true)
bool(true)
0

    
    
    

bool(false)
bool(true)
bool(true)
bool(true)
a
Comparison Operators
   

<?php
// Integers
echo 1 <=> 1, ' '; // 0
echo 1 <=> 2, ' '; // -1
echo 2 <=> 1, ' '; // 1

// Floats
echo 1.5 <=> 1.5, ' '; // 0
echo 1.5 <=> 2.5, ' '; // -1
echo 2.5 <=> 1.5, ' '; // 1

// Strings
echo "a" <=> "a", ' '; // 0
echo "a" <=> "b", ' '; // -1
echo "b" <=> "a", ' '; // 1

echo "a" <=> "aa", ' ';  // -1
echo "zz" <=> "aa", ' '; // 1

// Arrays
echo [] <=> [], ' ';               // 0
echo [1, 2, 3] <=> [1, 2, 3], ' '; // 0
echo [1, 2, 3] <=> [], ' ';        // 1
echo [1, 2, 3] <=> [1, 2, 1], ' '; // 1
echo [1, 2, 3] <=> [1, 2, 4], ' '; // -1

// Objects
$a = (object) ["a" => "b"];
$b = (object) ["a" => "b"];
echo $a <=> $b, ' '; // 0

$a = (object) ["a" => "b"];
$b = (object) ["a" => "c"];
echo $a <=> $b, ' '; // -1

$a = (object) ["a" => "c"];
$b = (object) ["a" => "b"];
echo $a <=> $b, ' '; // 1

// not only values are compared; keys must match
$a = (object) ["a" => "b"];
$b = (object) ["b" => "b"];
echo $a <=> $b, ' '; // 1

?>
Comparison Operators
For various types, comparison is done according to the following
  table (in order).
Comparison with Various Types
Boolean/null comparison
   

<?php
// Bool and null are compared as bool always
var_dump(1 == TRUE);  // TRUE - same as (bool) 1 == TRUE
var_dump(0 == FALSE); // TRUE - same as (bool) 0 == FALSE
var_dump(100 < TRUE); // FALSE - same as (bool) 100 < TRUE
var_dump(-10 < FALSE);// FALSE - same as (bool) -10 < FALSE
var_dump(min(-100, -10, NULL, 10, 100)); // NULL - (bool) NULL < (bool) -100 is FALSE < TRUE
?>
Boolean/null comparison
Transcription of standard array comparison
   

<?php
// Arrays are compared like this with standard comparison operators as well as the spaceship operator.
function standard_array_compare($op1, $op2)
{
    if (count($op1) < count($op2)) {
        return -1; // $op1 < $op2
    } elseif (count($op1) > count($op2)) {
        return 1; // $op1 > $op2
    }
    foreach ($op1 as $key => $val) {
        if (!array_key_exists($key, $op2)) {
            return 1;
        } elseif ($val < $op2[$key]) {
            return -1;
        } elseif ($val > $op2[$key]) {
            return 1;
        }
    }
    return 0; // $op1 == $op2
}
?>
Transcription of standard array comparison
Comparison of floating point numbers
Because of the way floats are represented internally, you
   should not test two floats for equality.
See the documentation for float for more information.
Be aware that PHP's type juggling is not always obvious when comparing values of different types,
   particularly comparing s to s or s to s. It is therefore generally
   advisable to use === and !== comparisons rather than
   == and != in most cases.
Incomparable Values
While identity comparison (=== and !==)
   can be applied to arbitrary values, the other comparison operators should only be
   applied to comparable values. The result of comparing incomparable values is
   undefined, and should not be relied upon.
strcasecmp
    strcmp
    Array operators
    Types
Ternary Operator
Another conditional operator is the "?:" (or ternary) operator.
   
    Assigning a default value
    

<?php
// Example usage for: Ternary Operator
$action = (empty($_POST['action'])) ? 'default' : $_POST['action'];

// The above is identical to this if/else statement
if (empty($_POST['action'])) {
    $action = 'default';
} else {
    $action = $_POST['action'];
}
?>

    
   
   The expression (expr1) ? (expr2) : (expr3)
   evaluates to expr2 if
   expr1 evaluates to , and
   expr3 if
   expr1 evaluates to .
Assigning a default value
It is possible to leave out the middle part of the ternary operator.
   Expression expr1 ?: expr3 evaluates to
   the result of expr1 if expr1
   evaluates to , and expr3 otherwise.
   expr1 is only evaluated once in this case.
Please note that the ternary operator is an expression, and that it
    doesn't evaluate to a variable, but to the result of an expression. This
    is important to know if you want to return a variable by reference.
    The statement return $var == 42 ? $a : $b; in a
    return-by-reference function will therefore not work and a warning is
    issued.
It is recommended to avoid "stacking" ternary expressions.
    PHP's behaviour when using more than one unparenthesized ternary operator within a single
    expression is non-obvious compared to other languages.
    Indeed prior to PHP 8.0.0, ternary expressions were evaluated left-associative,
    instead of right-associative like most other programming languages.
    Relying on left-associativity is deprecated as of PHP 7.4.0.
    As of PHP 8.0.0, the ternary operator is non-associative.
    
     Non-obvious Ternary Behaviour
     

<?php
// on first glance, the following appears to output 'true'
echo (true ? 'true' : false ? 't' : 'f');

// however, the actual output of the above is 't' prior to PHP 8.0.0
// this is because ternary expressions are left-associative

// the following is a more obvious version of the same code as above
echo ((true ? 'true' : false) ? 't' : 'f');

// here, one can see that the first expression is evaluated to 'true', which
// in turn evaluates to (bool) true, thus returning the true branch of the
// second ternary expression.
?>
Non-obvious Ternary Behaviour
Chaining of short-ternaries (?:), however, is stable and behaves reasonably.
    It will evaluate to the first argument that evaluates to a non-falsy value.  Note that undefined
    values will still raise a warning.
    
     Short-ternary chaining
     

<?php
echo 0 ?: 1 ?: 2 ?: 3, PHP_EOL; //1
echo 0 ?: 0 ?: 2 ?: 3, PHP_EOL; //2
echo 0 ?: 0 ?: 0 ?: 3, PHP_EOL; //3
?>
Short-ternary chaining
Null Coalescing Operator
Another useful shorthand operator is the "??" (or null coalescing) operator.
   
    Assigning a default value
    

<?php
// Example usage for: Null Coalesce Operator
$action = $_POST['action'] ?? 'default';

// The above is identical to this if/else statement
if (isset($_POST['action'])) {
    $action = $_POST['action'];
} else {
    $action = 'default';
}
?>

    
   
   The expression (expr1) ?? (expr2) evaluates to
   expr2 if expr1 is
   , and expr1 otherwise.
Assigning a default value
In particular, this operator does not emit a notice or warning if the left-hand side
   value does not exist, just like isset. This is especially
   useful on array keys.
Please note that the null coalescing operator is an expression, and that it
    doesn't evaluate to a variable, but to the result of an expression. This
    is important to know if you want to return a variable by reference.
    The statement return $foo ?? $bar; in a
    return-by-reference function will therefore not work and a warning is
    issued.
The null coalescing operator has low precedence. That means if mixing it
    with other operators (such as string concatenation or arithmetic operators)
    parentheses will likely be required.
Please note that the null coalescing operator allows for simple nesting:
    
     Nesting null coalescing operator
     

<?php

$foo = null;
$bar = null;
$baz = 1;
$qux = 2;

echo $foo ?? $bar ?? $baz ?? $qux; // outputs 1

?>
Nesting null coalescing operator
Operator Precedence
The precedence of an operator specifies how "tightly" it binds two
  expressions together. For example, in the expression 1 +
  5 * 3, the answer is 16 and not
  18 because the multiplication ("*") operator
  has a higher precedence than the addition ("+") operator.
  Parentheses may be used to force precedence, if necessary. For
  instance: (1 + 5) * 3 evaluates to
  18.
When operators have equal precedence their associativity decides
  how the operators are grouped. For example "-" is left-associative, so
  1 - 2 - 3 is grouped as (1 - 2) - 3
  and evaluates to -4. "=" on the other hand is
  right-associative, so $a = $b = $c is grouped as
  $a = ($b = $c).
Operators of equal precedence that are non-associative cannot be used
  next to each other, for example 1 < 2 > 1 is
  illegal in PHP. The expression 1 <= 1 == 1 on the
  other hand is legal, because the == operator has a lower
  precedence than the <= operator.
Associativity is only meaningful for binary (and ternary) operators.
  Unary operators are either prefix or postfix so this notion is not applicable.
  For example !!$a can only be grouped as !(!$a).
Use of parentheses, even when not strictly necessary, can often increase
  readability of the code by making grouping explicit rather than relying
  on the implicit operator precedence and associativity.
The following table lists the operators in order of precedence, with
  the highest-precedence ones at the top. Operators on the same line
  have equal precedence, in which case associativity decides grouping.
  
   Operator Precedence
   
    
     
      Associativity
      Operators
      Additional Information
     
    
    
     
      (n/a)
      
       clone
       new
      
      clone and new
     
     
      right
      **
      arithmetic
     
     
      (n/a)
      
       +
       -
       ++
       --
       ~
       (int)
       (float)
       (string)
       (array)
       (object)
       (bool)
       @
      
      
       arithmetic (unary + and -),
       increment/decrement,
       bitwise,
       type casting
       error control
      
     
     
      left
      instanceof
      
       type
      
     
     
      (n/a)
      !
      
       logical
      
     
     
      left
      
       *
       /
       %
      
      
       arithmetic
      
     
     
      left
      
       +
       -
       .
      
      
       arithmetic (binary + and -),
       array
       string (. prior to PHP 8.0.0)
      
     
     
      left
      
       
       
      
      
       bitwise
      
     
     
      left
      .
      
       string (as of PHP 8.0.0)
      
     
     
      left
      |
      
       pipe
      
     
     
      non-associative
      
       
       =
       
       =
      
      
       comparison
      
     
     
      non-associative
      
       ==
       !=
       ===
       !==
       
       =
      
      
       comparison
      
     
     
      left
      
      
       bitwise
       references
     
     
      left
      ^
      
       bitwise
      
     
     
      left
      |
      
       bitwise
      
     
     
      left
      
      
       logical
      
     
     
      left
      ||
      
       logical
      
     
     
      right
      ??
      
       null coalescing
      
     
     
      non-associative
      ? :
      
       ternary
       (left-associative prior to PHP 8.0.0)
      
     
     
      right
      
       =
       +=
       -=
       *=
       **=
       /=
       .=
       %=
       =
       |=
       ^=
       =
       =
       ??=
      
      
       assignment
      
     
     
      (n/a)
      yield from
      
       yield from
      
     
     
      (n/a)
      yield
      
       yield
      
     
     
      (n/a)
      print
      print
     
     
      left
      and
      
       logical
      
     
     
      left
      xor
      
       logical
      
     
     
      left
      or
      
       logical
      
     
     
      (n/a)
      throw
      
       throw
Operator Precedence
Associativity
   

<?php
$a = 3 * 3 % 5; // (3 * 3) % 5 = 4
var_dump($a);

$a = 1;
$b = 2;
$a = $b += 3; // $a = ($b += 3) -> $a = 5, $b = 5
var_dump($a, $b);
?>
Associativity
The ternary operator specifically requires the use of parenthesis to
  disambiguate precedence.
Explicit Precedence
   

<?php
$a = true ? 0 : (true ? 1 : 2);
var_dump($a);

// this is not allowed since PHP 8
// $a = true ? 0 : true ? 1 : 2;
?>
Explicit Precedence
Operator precedence and associativity only determine how expressions
  are grouped, they do not specify an order of evaluation. PHP does not
  (in the general case) specify in which order an expression is evaluated
  and code that assumes a specific order of evaluation should be avoided,
  because the behavior can change between versions of PHP or depending on
  the surrounding code.
  
   Undefined order of evaluation
   

<?php
$a = 1;
echo $a + $a++; // may print either 2 or 3

$i = 1;
$array[$i] = $i++; // may set either index 1 or 2
?>

   
  
  
   +, - and . precedence
   

<?php
$x = 4;
// this line might result in unexpected output:
echo "x minus one equals " . $x-1 . ", or so I hope\n";

// the desired precedence can be enforced by using parentheses:
echo "x minus one equals " . ($x-1) . ", or so I hope\n";

// this is not allowed, and throws a TypeError:
echo (("x minus one equals " . $x) - 1) . ", or so I hope\n";
?>

   
   
   

-1, or so I hope
-1, or so I hope
Fatal error: Uncaught TypeError: Unsupported operand types: string - int

   
  
  
   Prior to PHP 8, +, - and . had the same precedence
   

<?php
$x = 4;
// this line might result in unexpected output:
echo "x minus one equals " . $x-1 . ", or so I hope\n";

// because it is evaluated like this line (prior to PHP 8.0.0):
echo (("x minus one equals " . $x) - 1) . ", or so I hope\n";

// the desired precedence can be enforced by using parentheses:
echo "x minus one equals " . ($x-1) . ", or so I hope\n";
?>

   
   
   

-1, or so I hope
-1, or so I hope
x minus one equals 3, or so I hope
Undefined order of evaluation
+, - and . precedence
Prior to PHP 8, +, - and . had the same precedence
Although = has a lower precedence than
   most other operators, PHP will still allow expressions
   similar to the following: if (!$a = foo()),
   in which case the return value of foo() is
   put into $a.
Error Control Operators
PHP supports one error control operator: the at sign (@).
  When prepended to an expression in PHP, any diagnostic error that might
  be generated by that expression will be suppressed.
If a custom error handler function is set with
  set_error_handler, it will still be called even though
  the diagnostic has been suppressed.
Prior to PHP 8.0.0, the error_reporting called inside the custom error handler
   always returned 0 if the error was suppressed by the @ operator.
   As of PHP 8.0.0, it returns the value of this (bitwise) expression:
   E_ERROR | E_CORE_ERROR | E_COMPILE_ERROR | E_USER_ERROR | E_RECOVERABLE_ERROR | E_PARSE.
Any error message generated by the expression is available in the "message"
  element of the array returned by error_get_last.
  The result of that function will change on each error, so it needs to be checked early.
Intentional file error
   

<?php
$my_file = @file ('non_existent_file') or
    die ("Failed opening file: error was '" . error_get_last()['message'] . "'");
?>
Intentional file error
Suppressing Expressions
   

<?php
// this works for any expression, not just functions:
$value = @$cache[$key];
// will not issue a notice if the index $key doesn't exist.
?>
Suppressing Expressions
The @-operator works only on
   expressions.
   A simple rule of thumb is: if one can take the value of something,
   then one can prepend the @ operator to it.
   For instance, it can be prepended to variables, functions calls,
   certain language construct calls (e.g. include),
   and so forth.
   It cannot be prepended to function or class definitions,
   or conditional structures such as if and
   , and so forth.
Prior to PHP 8.0.0, it was possible for the @ operator
   to disable critical errors that will terminate script execution.
   For example, prepending @ to a call of a function
   which did not exist, by being unavailable or mistyped, would cause
   the script to terminate with no indication as to why.
error_reporting
    Error Handling and Logging functions
String Operators
There are two string operators. The first is the
  concatenation operator ('.'), which returns the concatenation of its
  right and left arguments. The second is the concatenating assignment
  operator ('.='), which appends the argument on the right side to
  the argument on the left side. Please read Assignment
  Operators for more information.
String Concatenating
   

<?php
$a = "Hello ";
$b = $a . "World!"; // now $b contains "Hello World!"
var_dump($b);

$a = "Hello ";
$a .= "World!";     // now $a contains "Hello World!"
var_dump($a);
?>
String Concatenating
String type
    String functions
Incrementing/Decrementing Operators
PHP supports pre- and post-increment and decrement operators.
  Those unary operators allow to increment or decrement the value by one.
Increment/decrement Operators
Examples of Increment/Decrement
   

<?php
echo 'Post-increment:', PHP_EOL;
$a = 5;
var_dump($a++);
var_dump($a);

echo 'Pre-increment:', PHP_EOL;
$a = 5;
var_dump(++$a);
var_dump($a);

echo 'Post-decrement:', PHP_EOL;
$a = 5;
var_dump($a--);
var_dump($a);

echo 'Pre-decrement:', PHP_EOL;
$a = 5;
var_dump(--$a);
var_dump($a);
?>

   
   
   

Post-increment:
int(5)
int(6)
Pre-increment:
int(6)
int(6)
Post-decrement:
int(5)
int(4)
Pre-decrement:
int(4)
int(4)

   
  

  
   
    The increment and decrement operators have no effect on values
    of type bool.
    A E_WARNING is emitted as of PHP 8.3.0,
    because this will implicitly cast the value to int in the future.
   
   
    The decrement operator has no effect on values
    of type null.
    A E_WARNING is emitted as of PHP 8.3.0,
    because this will implicitly cast the value to int in the future.
   
   
    The decrement operator has no effect on non-
    numeric string.
    A E_WARNING is emitted as of PHP 8.3.0,
    because a TypeError will be thrown in the future.
   
  
  
   
    Internal objects that support overloading addition and/or subtraction
    can also be incremented and/or decremented.
    One such internal object is GMP.
Examples of Increment/Decrement
The increment and decrement operators have no effect on values
    of type bool.
    A E_WARNING is emitted as of PHP 8.3.0,
    because this will implicitly cast the value to int in the future.
The decrement operator has no effect on values
    of type null.
    A E_WARNING is emitted as of PHP 8.3.0,
    because this will implicitly cast the value to int in the future.
The decrement operator has no effect on non-
    numeric string.
    A E_WARNING is emitted as of PHP 8.3.0,
    because a TypeError will be thrown in the future.
Internal objects that support overloading addition and/or subtraction
    can also be incremented and/or decremented.
    One such internal object is GMP.
PERL string increment feature
This feature is soft-deprecated as of PHP 8.3.0.
    The str_increment function should be used instead.
It is possible to increment a non-
   numeric string
   in PHP. The string must be an alphanumerical ASCII string.
   Which increments letters up to the next letter, when reaching the letter
   Z the increment is carried to the value on the left.
   For example, $a = 'Z'; $a++; turns $a
   into 'AA'.
PERL string increment example
If the alphanumerical string can be interpreted as a
    numeric string
    it will be cast to an int or float.
    This is particularly an issue with strings that look like a floating point
    numbers written in exponential notation.
    The str_increment function does not suffer from
    these implicit type cast.
Alphanumerical string converted to float
This is because the value "5e0" is interpreted
     as a float and cast to the value 5.0
     before being incremented.
Assignment Operators
The basic assignment operator is "=". Your first inclination might
  be to think of this as "equal to". Don't. It really means that the
  left operand gets set to the value of the expression on the
  right (that is, "gets set to").
The value of an assignment expression is the value assigned. That
  is, the value of "$a = 3" is 3. This allows you to do some tricky
  things:
  
   Nested Assignments
   

<?php
$a = ($b = 4) + 5; // $a is equal to 9 now, and $b has been set to 4.
var_dump($a);
?>
Nested Assignments
In addition to the basic assignment operator, there are "combined
  operators" for all of the binary
  arithmetic, array union and string operators that allow you to use a value in an
  expression and then set its value to the result of that expression. For
  example:
  
   Combined Assignments
   

<?php
$a = 3;
$a += 5; // sets $a to 8, as if we had said: $a = $a + 5;
$b = "Hello ";
$b .= "There!"; // sets $b to "Hello There!", just like $b = $b . "There!";

var_dump($a, $b);
?>
Combined Assignments
Note that the assignment copies the original variable to the new
  one (assignment by value), so changes to one will not affect the
  other. This may also have relevance if you need to copy something
  like a large array inside a tight loop.
An exception to the usual assignment by value behaviour within PHP occurs
  with objects, which are assigned by reference.
  Objects may be explicitly copied via the clone keyword.
Assignment by Reference
Assignment by reference is also supported, using the
   "$var = &$othervar;" syntax.
   Assignment by reference means that both variables end up pointing at the
   same data, and nothing is copied anywhere.
Assigning by reference
    

<?php
$a = 3;
$b = &$a; // $b is a reference to $a

print "$a\n"; // prints 3
print "$b\n"; // prints 3

$a = 4; // change $a

print "$a\n"; // prints 4
print "$b\n"; // prints 4 as well, since $b is a reference to $a, which has
              // been changed
?>
Assigning by reference
The new
   operator returns a reference automatically, as such assigning the result of
   new by reference is an error.
new Operator By-Reference
    

<?php
class C {}

$o = &new C;
?>

    
    
    

Parse error: syntax error, unexpected token ";", expecting "("
new Operator By-Reference
More information on references and their potential uses can be found in
   the References Explained
   section of the manual.
Arithmetic Assignment Operators
Bitwise Assignment Operators
Other Assignment Operators
arithmetic operators
    bitwise operators
    null coalescing operator
New Classes and Interfaces
cURL
CURLStringFile
FileInfo
finfo
FTP
FTP\Connection
IMAP
IMAP\Connection
Intl
IntlDatePatternGenerator
LDAP
LDAP\Connection
LDAP\Result
LDAP\ResultEntry
PgSQL
PgSql\Connection
PgSql\Lob
PgSql\Result
PSpell
PSpell\Config
PSpell\Dictionary
Reflection
ReflectionFiber
New Functions
PHP Core
array_is_list
GD
imagecreatefromavif
imageavif
MySQLi
mysqli_result::fetch_column
mysqli_fetch_column
Process Control
pcntl_rfork
Reflection
ReflectionFunctionAbstract::getClosureUsedVariables
Standard
fsync
fdatasync
Sodium
XChaCha20
sodium_crypto_stream_xchacha20
sodium_crypto_stream_xchacha20_keygen
sodium_crypto_stream_xchacha20_xor
Ristretto255
Ristretto255 functions are available as of libsodium 1.0.18.
sodium_crypto_core_ristretto255_add
sodium_crypto_core_ristretto255_from_hash
sodium_crypto_core_ristretto255_is_valid_point
sodium_crypto_core_ristretto255_random
sodium_crypto_core_ristretto255_scalar_add
sodium_crypto_core_ristretto255_scalar_complement
sodium_crypto_core_ristretto255_scalar_invert
sodium_crypto_core_ristretto255_scalar_mul
sodium_crypto_core_ristretto255_scalar_negate
sodium_crypto_core_ristretto255_scalar_random
sodium_crypto_core_ristretto255_scalar_reduce
sodium_crypto_core_ristretto255_scalar_sub
sodium_crypto_core_ristretto255_sub
sodium_crypto_scalarmult_ristretto255
sodium_crypto_scalarmult_ristretto255_base
New Global Constants
cURL
CURLOPT_DOH_URL
CURLOPT_ISSUERCERT_BLOB
CURLOPT_PROXY_ISSUERCERT
CURLOPT_PROXY_ISSUERCERT_BLOB
CURLOPT_PROXY_SSLCERT_BLOB
CURLOPT_PROXY_SSLKEY_BLOB
CURLOPT_SSLCERT_BLOB
CURLOPT_SSLKEY_BLOB
GD
IMG_AVIF
IMG_WEBP_LOSSLESS
MySQLi
MYSQLI_REFRESH_REPLICA
This constant has been added as a replacement for
     MYSQLI_REFRESH_SLAVE,
     in line with an upstream change in MySQL.
     The old constant is still available for backwards-compatibility reasons,
     but may be deprecated/removed in the future.
PCNTL
PRIO_DARWIN_BG
PRIO_DARWIN_THREAD
POSIX
POSIX_RLIMIT_KQUEUES
POSIX_RLIMIT_NPTS
Sockets
The following socket options are now defined if they are supported:
SO_ACCEPTFILTER
SO_DONTTRUNC
SO_WANTMORE
SO_MARK
TCP_DEFER_ACCEPT
Sodium
SODIUM_CRYPTO_STREAM_XCHACHA20_NONCEBYTES
SODIUM_CRYPTO_STREAM_XCHACHA20_KEYBYTES
SODIUM_CRYPTO_SCALARMULT_RISTRETTO255_BYTES
SODIUM_CRYPTO_SCALARMULT_RISTRETTO255_SCALARBYTES
SODIUM_CRYPTO_CORE_RISTRETTO255_BYTES
SODIUM_CRYPTO_CORE_RISTRETTO255_HASHBYTES
SODIUM_CRYPTO_CORE_RISTRETTO255_SCALARBYTES
SODIUM_CRYPTO_CORE_RISTRETTO255_NONREDUCEDSCALARBYTES
Tokenizer
T_READONLY
Backward Incompatible Changes
PHP Core
$GLOBALS Access Restrictions
Access to the $GLOBALS array is now subject to
    a number of restrictions.
    Read and write access to individual array elements like
    $GLOBALS['var'] continues to work as-is.
    Read-only access to the entire $GLOBALS array also
    continues to be supported.
    However, write access to the entire $GLOBALS array
    is no longer supported. For example, array_pop($GLOBALS)
    will result in an error.
Usage of static Variables in Inherited Methods
When a method using static variables is inherited (but not overridden), the
    inherited method will now share static variables with the parent method.
    
     

<?php
class A {
    public static function counter() {
        static $counter = 0;
        $counter++;
        return $counter;
    }
}
class B extends A {}
var_dump(A::counter()); // int(1)
var_dump(A::counter()); // int(2)
var_dump(B::counter()); // int(3), previously int(1)
var_dump(B::counter()); // int(4), previously int(2)
?>

     
    

    This means that static variables in methods now behave the same way as
    static properties.
Optional parameters specified before required parameters
An optional parameter
    specified before required parameters is now always treated as required,
    even when called using
    named arguments.
    As of PHP 8.0.0, but prior to PHP 8.1.0, the below emits a deprecation notice
    on the definition, but runs successfully when called. As of PHP 8.1.0, an error
    of class ArgumentCountError is thrown, as it would be when
    called with positional arguments.

    
     

<?php
function makeyogurt($container = "bowl", $flavour)
{
    return "Making a $container of $flavour yogurt.\n";
}
try
{
    echo makeyogurt(flavour: "raspberry");
}
catch (Error $e)
{
    echo get_class($e), ' - ', $e->getMessage(), "\n";
}
?>

     
     
     

Deprecated: Required parameter $flavour follows optional parameter $container
 in example.php on line 3
Making a bowl of raspberry yogurt.

     
     
     

Deprecated: Optional parameter $container declared before required parameter
 $flavour is implicitly treated as a required parameter in example.php on line 3
ArgumentCountError - makeyogurt(): Argument #1 ($container) not passed
Note that a default value of  can be used before required parameters to
    specify a nullable type,
    but the parameter will still be required.
Return Type Compatibility with Internal Classes
Most non-final internal methods now require overriding methods to declare
    a compatible return type, otherwise a deprecated notice is emitted during
    inheritance validation.
    In case the return type cannot be declared for an overriding method due to
    PHP cross-version compatibility concerns,
    a ReturnTypeWillChange attribute can be added to silence
    the deprecation notice.
New Keywords
readonly is a keyword now. However, it still may be used
    as function name.
never is now a reserved word, so it cannot be used to name a class,
    interface or trait, and is also prohibited from being used in namespaces.
Resource to Object Migration
Several s have been migrated to s.
   Return value checks using is_resource should be replaced with checks for .
The FileInfo functions now accept and return
     finfo objects instead of
     fileinfo s.
The FTP functions now accept and return
     FTP\Connection objects instead of
     ftp s.
The IMAP functions now accept and return
     IMAP\Connection objects instead of
     imap s.
The LDAP functions now accept and return
     LDAP\Connection objects instead of
     ldap link s.
The LDAP functions now accept and return
     LDAP\Result objects instead of
     ldap result s.
The LDAP functions now accept and return
     LDAP\ResultEntry objects instead of
     ldap result entry s.
The PgSQL functions now accept and return
     PgSql\Connection objects instead of
     pgsql link s.
The PgSQL functions now accept and return
     PgSql\Result objects instead of
     pgsql result s.
The PgSQL functions now accept and return
     PgSql\Lob objects instead of
     pgsql large object s.
The PSpell functions now accept and return
     PSpell\Dictionary objects instead of
     pspell s.
The PSpell functions now accept and return
     PSpell\Config objects instead of
     pspell config s.
MySQLi
mysqli_fetch_fields, and
   mysqli_fetch_field_direct will now always return
   0 for the max_length.
   This information can be computed by iterating over the result set,
   and taking the maximum length. This is what PHP was doing
   internally previously.
The MYSQLI_STMT_ATTR_UPDATE_MAX_LENGTH
   option no longer has any effect.
The MYSQLI_STORE_RESULT_COPY_DATA
   option no longer has any effect. Passing any value to the
   mode parameter of
   mysqli::store_result no longer has any effect.
mysqli::connect now returns  instead of  on success.
The default error handling mode has been changed from "silent" to "exceptions"
   See the MySQLi reporting mode
   page for more details on what this entails,
   and how to explicitly set this attribute.
   To restore the previous behaviour use:
   mysqli_report(MYSQLI_REPORT_OFF);
Classes extending mysqli_stmt::execute
   are now required to specify the additional optional parameter.
MySQLnd
The mysqlnd.fetch_data_copy
   INI directive has been removed.
   This should not result in user-visible behavior changes.
OpenSSL
EC private keys will now be exported in PKCS#8 format rather than
   traditional format, just like all other keys.
openssl_pkcs7_encrypt and
   openssl_cms_encrypt will now to default using
   AES-128-CBC rather than RC2-40. The RC2-40 cipher is considered
   insecure and not enabled by default by OpenSSL 3.
PHP Data Objects
PDO::ATTR_STRINGIFY_FETCHES now stringifies values
   of type  to "0" or
   "1". Previously s were not stringified.
Calling PDOStatement::bindColumn with
   PDO::PARAM_LOB will now constantly bind a stream
   result when PDO::ATTR_STRINGIFY_FETCHES is not enabled.
   Previously, the result would either be a stream or a string depending on
   the used database driver and the time the binding is performed.
MySQL Driver
Integers and floats in result sets will now be returned using native
    PHP types instead of s when using emulated prepared statements.
    This matches the behavior of native prepared statements.
    The previous behaviour can be restored by enabling the
    PDO::ATTR_STRINGIFY_FETCHES option.
SQLite Driver
Integers and floats in results sets will now be returned using native
    PHP types.
    The previous behaviour can be restored by enabling the
    PDO::ATTR_STRINGIFY_FETCHES option.
Phar
To comply with the ArrayAccess interface,
   Phar::offsetUnset and
   PharData::offsetUnset no longer return a .
Standard
version_compare no longer accepts undocumented operator abbreviations.
htmlspecialchars,
   htmlentities,
   htmlspecialchars_decode,
   html_entity_decode,
   and get_html_translation_table
   now use ENT_QUOTES | ENT_SUBSTITUTE rather than
   ENT_COMPAT by default.
   This means that ' is escaped to
   #039; while previously nothing was done.
   Additionally, malformed UTF-8 will be replaced by a Unicode substitution
   character, instead of resulting in an empty string.
debug_zval_dump now prints the refcount of a reference
   wrappers with their refcount, instead of only prepending
    to the value.
   This more accurately models reference representation since PHP 7.0.
debug_zval_dump now prints interned
   instead of a dummy refcount for interned strings and immutable arrays.
Standard PHP Library (SPL)
SplFixedArray, will now be JSON encoded like an
Other Changes
Changes in SAPI Modules
CLI
Using -a without the readline extension will now result in an error.
    Previously, -a without readline had the same behavior as
    calling php without any arguments, apart from printing an additional
    "Interactive mode enabled" message.
    This mode was not interactive.
PHPDBG
Remote functionality from phpdbg has been removed.
Changed Functions
Core
The order of properties used in , var_dump,
    serialize, object comparison, etc. was changed.
    Properties are now ordered naturally according to their declaration
    and inheritance. Properties declared in a base class are going
    to be before the child properties.
This order is consistent with internal layout of properties in
    zend_object structure and repeats the order in
    default_properties_table[] and properties_info_table[].
    The old order was not documented and was caused by class inheritance implementation details.
Filter
The FILTER_FLAG_ALLOW_OCTAL flag of the
    FILTER_VALIDATE_INT filter
    now accept octal string with the leading octal prefix
    ("0o"/"0O").
GMP
All GMP functions now accept octal string with the leading octal prefix
    ("0o"/"0O").
PDO ODBC
PDO::getAttribute with
    PDO::ATTR_SERVER_INFO and
    PDO::ATTR_SERVER_VERSION
    now return values instead of throwing PDOException.
Reflection
ReflectionProperty::setAccessible and
    ReflectionMethod::setAccessible
    no longer have an effect.
    Properties and methods are now always considered accessible via Reflection.
Standard
syslog is now binary safe.
Other Changes to Extensions
GD
imagewebp can now do lossless WebP encoding
    by passing IMG_WEBP_LOSSLESS as the quality.
This constant is only defined, if the used libgd supports
    lossless WebP encoding.
MySQLi
mysqli_stmt::next_result and
    mysqli::fetch_all
    are now available when linking against libmysqlclient.
OpenSSL
The OpenSSL extension now requires at least OpenSSL version 1.0.2.
OpenSSL 3.0 is now supported. Be aware that many ciphers are no longer
      enabled by default (part of the legacy provider), and that parameter
      validation (e.g. minimum key sizes) is stricter now.
Phar
SHA256 is now used by default for signatures.
Added support for OpenSSL_SHA256 and OpenSSL_SHA512 signatures.
SNMP
Added support for SHA256 and SHA512 for the security protocol.
Standard
--with-password-argon2 now uses pkg-config to detect libargon2.
    As such, an alternative libargon2 location should now be specified using
    PKG_CONFIG_PATH.
Changes to INI File Handling
The log_errors_max_len
     INI directive has been removed.
     It no longer had an effect since PHP 8.0.0.
A leading dollar in a quoted string can now be escaped: "\${" will now be
     interpreted as a string with contents ${.
Backslashes in double quoted strings are now more consistently treated as
     escape characters. Previously, "foo\\" followed by
     something other than a newline was not considered as a terminated string.
     It is now interpreted as a string with contents foo\.
     However, as an exception, the string "foo\"
     followed by a newline will continue to be treated as a valid string with
     contents foo\ rather than an unterminated string.
     This exception exists to support naive uses of Windows file paths such as
     "C:\foo\".
New Features
PHP Core
Integer Octal Literal Prefix
Octal integers can now use an explicit
    0o/0O
    prefix in integer literals,
    similarly to binary and hexadecimal integer literals.
    
     

<?php
014;  // Non-prefix octal literal
0o14; // Prefixed octal literal
?>
Array Unpacking with String Keys
Added support for array unpacking with strings keys.
    
     

<?php
$arr1 = [1, 'a' => 'b'];
$arr2 = [...$arr1, 'c' => 'd']; //[1, 'a' => 'b', 'c' => 'd']
?>
Named Argument After Argument Unpacking
It is now possible to specify named arguments after an argument unpack.
    
    e.g.
    foo(...$args, named: $arg).
full-path Key for File Uploads
File uploads now provide an additional full_path key,
    which contains the full path (rather than just the basename) of the uploaded file.
    This is intended for use in conjunction with "upload webkitdirectory".
Enumerations
Support for Enumerations has been added.
Fibers
Support for Fibers has been added.
First Class Callable Syntax
Closures for callables can now be created using the syntax myFunc(...),
    which is identical to Closure::fromCallable('myFunc').
The ... is part of the syntax, and not an omission.
Intersection Types
Support for intersection types has been added.
Intersection types cannot be used together with
     
      union types
Never type
A new return only type  has been added.
    This indicates that a function either exit,
    throws an exception, or doesn't terminate.
in Initializers
It is now possible to use new ClassName() expressions as the
    default value of a parameter, static variable, global constant initializers,
    and as attribute arguments.
    Objects can also be passed to define now.
Readonly properties
Support for readonly has been added.
Final class constants
Added support for the final modifier for class constants.
    Also, interface constants become overridable by default.
CURL
Added the CURLOPT_DOH_URL option.
Added options for blob certificate when libcurl = 7.71.0:
CURLOPT_ISSUERCERT_BLOB
CURLOPT_PROXY_ISSUERCERT
CURLOPT_PROXY_ISSUERCERT_BLOB
CURLOPT_PROXY_SSLCERT_BLOB
CURLOPT_PROXY_SSLKEY_BLOB
CURLOPT_SSLCERT_BLOB
CURLOPT_SSLKEY_BLOB
Added CURLStringFile, which can be used to post
   a file from a  rather than a file:
   
    

<?php
$file = new CURLStringFile($data, 'filename.txt', 'text/plain');
curl_setopt($curl, CURLOPT_POSTFIELDS, ['file' => $file]);
?>
FPM
Added openmetrics status format. It can be used by Prometheus to fetch FPM
   metrics.
Added new pool option for the dynamic process manager called
   pm.max_spawn_rate. It allows to start a number of children
   at a faster rate when dynamic pm is selected.
   The default value is 32 which was the previous
   hard coded value.
GD
Avif support is now available through
   imagecreatefromavif and
   imageavif,
   if libgd has been built with Avif support.
Hash
The following functions hash,
   hash_file, and hash_init
   now support an additional optional options
   argument, which can be used to pass algorithm specific data.
MurmurHash3
Added support for MurmurHash3 with streaming
    support. The following variants are implemented:
murmur3a, 32-bit hash
murmur3c, 128-bit hash for x86
murmur3f, 128-bit hash for x64
The initial hash state can be passed through the seed
    key in the options array, for example:

    
     
      
<?php
$h = hash("murmur3f", $data, options: ["seed" => 42]);
echo $h, "\n";
?>

     
    

    A valid seed value is within the range from 0
    to the platform defined UINT_MAX, usually
    4294967295.
xxHash
Added support for xxHash.
    The following variants are implemented:
xxh32, 32-bit hash
xxh64, 64-bit hash
xxh3, 64-bit hash
xxh128, 128-bit hash
The initial hash state can be passed through the seed
    key in the options array, for example:

    
     
      
<?php
$h = hash("xxh3", $data, options: ["seed" => 42]);
echo $h, "\n";
?>

     
    

    Secret usage is supported through passing the secret
    key in the options array, too:

    
     
      
<?php
$h = hash("xxh3", $data, options: ["secret" => "at least 136 bytes long secret here"]);
echo $h, "\n";
?>

     
    

    The quality of the custom secret is crucial for the quality of the resulting hash.
    It is highly recommended for the secret to use the best possible entropy.
MySQLi
New INI directive mysqli.local_infile_directory
The mysqli.local_infile_directory
    INI directive has been added, which can be used to specify a directory from
    which files are allowed to be loaded. It is only meaningful if
    mysqli.allow_local_infile
    is not enabled, as all directories are allowed in that case.
Binding parameters in execute
It is now possible to bind parameters by passing them as an array to
    mysqli_stmt::execute. All values will be bound as
    strings. Only list arrays are allowed. This new feature is not available
    when MySQLi is compiled with libmysqlclient.
    
    
     

<?php
$stmt = $mysqli->prepare('INSERT INTO users(id, name) VALUES(?,?)');
$stmt->execute([1, $username]);
?>
New method mysqli_result::fetch_column
mysqli_result::fetch_column
    has been added to allow fetching a single scalar value from the result set.
    The new method accepts an optional 0-based column
    parameter of type  specifying which column to fetch from.
    
    
     

<?php
$result = $mysqli->query('SELECT username FROM users WHERE id = 123');
echo $result->fetch_column();
?>
PDO
The PDO::MYSQL_ATTR_LOCAL_INFILE_DIRECTORY attribute
   has been added, which can be used to specify a directory from which files
   are allowed to be loaded.
   It is only meaningful if PDO::MYSQL_ATTR_LOCAL_INFILE
   is not enabled, as all directories are allowed in that case.
PDO_SQLite
SQLite's "file:" DSN syntax is now supported,
   which allows specifying additional flags.
   This feature is not available if open_basedir is set.
   
    

<?php
new PDO('sqlite:file:path/to/sqlite.db?mode=ro')
?>
POSIX
Added POSIX_RLIMIT_KQUEUES and POSIX_RLIMIT_NPTS.
   These rlimits are only available on FreeBSD.
Standard
fputcsv now accepts a new
   eol argument which allows to define a custom
   End of Line sequence, the default remains the same and is "\n".
SPL
SplFileObject::fputcsv now accepts a new
   eol argument which allows to define a custom
   End of Line sequence, the default remains the same and is "\n".
Deprecated Features
PHP Core
Implementing Serializable without
    __serialize and __unserialize
Either only the new methods should be implemented, if no support for
    PHP prior to version 7.4 is provided, or both should be implemented.
Passing  to non-nullable parameters of built-in functions
Scalar types for built-in functions are nullable by default.
    This behaviour is deprecated to align with the behaviour of user-defined
    functions, where scalar types need to be marked as nullable explicitly.

    
     

<?php
var_dump(str_contains("foobar", null));
// Deprecated: Passing null to parameter #2 ($needle) of type string
//             is deprecated
?>
Implicit incompatible  to  conversions
The implicit conversion of  to  which
    leads to a loss in precision is now deprecated.
    This affects  keys,  type declarations in coercive mode,
    and operators working on s.

    
     

<?php
$a = [];
$a[15.5]; // deprecated, as key value loses the 0.5 component
$a[15.0]; // ok, as 15.0 == 15
?>
Calling a static element on a trait
Calling a static method, or accessing a
    static property directly on a trait is deprecated.
    Static methods and properties should only be accessed on a class using the trait.
Returning a non- from __sleep
Returning a value which is not an  from
    __sleep() now generates a diagnostic.
Returning by reference from a void function
<?php
function &test(): void {}
?>

     
    
    Such a function is contradictory, and already emits the following
    E_NOTICE when called:
    Only variable references should be returned by reference.
Autovivification from
Autovivification is the process of creating a new  when
    appending to a value.
    Autovivification is prohibited from scalar values,  however
    was an exception. This is now deprecated.

    
     

<?php
$arr = false;
$arr[] = 2;   // deprecated
?>
Autovivification from  and undefined values is still allowed:
     
      

<?php
// From undefined
$arr[] = 'some value';
$arr['doesNotExist'][] = 2;
// From null
$arr = null;
$arr[] = 2;
?>
ctype
Verifying non-string arguments
Passing a non-string argument is deprecated.
    In the future, the argument will be interpreted as a string instead
    of an ASCII codepoint.
    Depending on the intended behavior, the argument should either be
    cast to  or an explicit call to
    chr should be made.
    All ctype_*() functions are affected.
Date
date_sunrise and date_sunset
   have been deprecated in favor of date_sun_info.
strptime has been deprecated.
   Use date_parse_from_format instead (for locale-independent parsing),
   or IntlDateFormatter::parse (for locale-dependent parsing).
strftime and gmstrftime have been deprecated.
   Use date instead (for locale-independent formatting),
   or IntlDateFormatter::format (for locale-dependent formatting).
Filter
The FILTER_SANITIZE_STRING and
   FILTER_SANITIZE_STRIPPED filters are deprecated.
The filter.default
   INI directive is deprecated.
GD
The num_points of imagepolygon,
   imageopenpolygon and imagefilledpolygon
   has been deprecated.
Hash
The mhash,
   mhash_keygen_s2k,
   mhash_count,
   mhash_get_block_size,
   and mhash_get_hash_name have been deprecated.
   Use the hash_*() functions instead.
IMAP
The NIL constant has been deprecated.
   Use 0 instead.
Intl
Calling IntlCalendar::roll with a
    argument is deprecated.
   Use 1 and -1 instead of
    and  respectively.
Multibyte String
Calling mb_check_encoding without any arguments
   is deprecated.
MySQLi
The mysqli_driver::$driver_version property
   has been deprecated.
   It was meaningless and outdated, use PHP_VERSION_ID
   instead.
Calling mysqli::get_client_info or
   mysqli_get_client_info with the
   mysqli argument has been deprecated.
   Call mysqli_get_client_info without any arguments
   to obtain the version information of the client library.
The mysqli::init method has been deprecated.
   Replace calls to parent::init with
   parent::__construct.
OCI8
The oci8.old_oci_close_semantics
   INI directive is deprecated.
ODBC
odbc_result_all has been deprecated.
PDO
The PDO::FETCH_SERIALIZE fetch mode has been deprecated.
PgSQL
Not passing the connection argument to all pgsql_*()
   functions has been deprecated.
SOAP
The ssl_method option of
   SoapClient::__construct has been deprecated
   in favor of SSL stream context options.
Standard
Calling key, current,
   next, prev,
   reset, or end
   on s is deprecated.
   Either convert the  to an  using get_mangled_object_vars
   first, or use the methods provided by a class that implements
   Iterator, such as ArrayIterator, instead.
The auto_detect_line_endings
   INI directive is deprecated.
   If necessary, handle "\r" line breaks manually instead.
The FILE_BINARY and
   FILE_TEXT constants have been deprecated.
   They never had any effect.
New functions
PHP Core
stream_isatty
sapi_windows_vt100_support
SPL
spl_object_id
DOM
DomNodeList::count
DOMNamedNodeMap::count
FTP
ftp_append
GD
imagesetclip
imagegetclip
imageopenpolygon
imageresolution
imagecreatefrombmp
imagebmp
Hash
hash_hmac_algos
LDAP
ldap_parse_exop
ldap_exop
ldap_exop_passwd
ldap_exop_whoami
Multibyte String
mb_chr
mb_ord
mb_scrub
Oracle OCI8
oci_register_taf_callback
oci_unregister_taf_callback
Sockets
socket_addrinfo_lookup
socket_addrinfo_connect
socket_addrinfo_bind
socket_addrinfo_explain
Sodium
sodium_add
sodium_bin2hex
sodium_compare
sodium_crypto_aead_aes256gcm_decrypt
sodium_crypto_aead_aes256gcm_encrypt
sodium_crypto_aead_aes256gcm_is_available
sodium_crypto_aead_aes256gcm_keygen
sodium_crypto_aead_chacha20poly1305_decrypt
sodium_crypto_aead_chacha20poly1305_encrypt
sodium_crypto_aead_chacha20poly1305_ietf_decrypt
sodium_crypto_aead_chacha20poly1305_ietf_encrypt
sodium_crypto_aead_chacha20poly1305_ietf_keygen
sodium_crypto_aead_chacha20poly1305_keygen
sodium_crypto_auth_keygen
sodium_crypto_auth_verify
sodium_crypto_auth
sodium_crypto_box_keypair_from_secretkey_and_publickey
sodium_crypto_box_keypair
sodium_crypto_box_open
sodium_crypto_box_publickey_from_secretkey
sodium_crypto_box_publickey
sodium_crypto_box_seal_open
sodium_crypto_box_seal
sodium_crypto_box_secretkey
sodium_crypto_box_seed_keypair
sodium_crypto_box
sodium_crypto_generichash_final
sodium_crypto_generichash_init
sodium_crypto_generichash_keygen
sodium_crypto_generichash_update
sodium_crypto_generichash
sodium_crypto_kdf_derive_from_key
sodium_crypto_kdf_keygen
sodium_crypto_kx_client_session_keys
sodium_crypto_kx_keypair
sodium_crypto_kx_publickey
sodium_crypto_kx_secretkey
sodium_crypto_kx_seed_keypair
sodium_crypto_kx_server_session_keys
sodium_crypto_pwhash_scryptsalsa208sha256_str_verify
sodium_crypto_pwhash_scryptsalsa208sha256_str
sodium_crypto_pwhash_scryptsalsa208sha256
sodium_crypto_pwhash_str_verify
sodium_crypto_pwhash_str
sodium_crypto_pwhash
sodium_crypto_scalarmult_base
sodium_crypto_scalarmult
sodium_crypto_secretbox_keygen
sodium_crypto_secretbox_open
sodium_crypto_secretbox
sodium_crypto_shorthash_keygen
sodium_crypto_shorthash
sodium_crypto_sign_detached
sodium_crypto_sign_ed25519_pk_to_curve25519
sodium_crypto_sign_ed25519_sk_to_curve25519
sodium_crypto_sign_keypair_from_secretkey_and_publickey
sodium_crypto_sign_keypair
sodium_crypto_sign_open
sodium_crypto_sign_publickey_from_secretkey
sodium_crypto_sign_publickey
sodium_crypto_sign_secretkey
sodium_crypto_sign_seed_keypair
sodium_crypto_sign_verify_detached
sodium_crypto_sign
sodium_crypto_stream_keygen
sodium_crypto_stream_xor
sodium_crypto_stream
sodium_hex2bin
sodium_increment
sodium_memcmp
sodium_memzero
sodium_pad
sodium_unpad
ZIP
ZipArchive::count
ZipArchive::setEncryptionName
ZipArchive::setEncryptionIndex
New global constants
PHP Core
PHP_FLOAT_DIG
PHP_FLOAT_EPSILON
PHP_FLOAT_MIN
PHP_FLOAT_MAX
PHP_OS_FAMILY
File Information
FILEINFO_EXTENSION
JSON
JSON_INVALID_UTF8_IGNORE
JSON_INVALID_UTF8_SUBSTITUTE
GD
IMG_EFFECT_MULTIPLY
IMG_BMP
LDAP
LDAP_EXOP_START_TLS
LDAP_EXOP_MODIFY_PASSWD
LDAP_EXOP_REFRESH
LDAP_EXOP_WHO_AM_I
LDAP_EXOP_TURN
Password Hashing
PASSWORD_ARGON2I
PASSWORD_ARGON2_DEFAULT_MEMORY_COST
PASSWORD_ARGON2_DEFAULT_TIME_COST
PASSWORD_ARGON2_DEFAULT_THREADS
PCRE
PREG_UNMATCHED_AS_NULL
PDO
PDO::PARAM_STR_NATL
PDO::PARAM_STR_CHAR
PDO::ATTR_DEFAULT_STR_PARAM
Sodium
SODIUM_LIBRARY_VERSION
SODIUM_LIBRARY_MAJOR_VERSION
SODIUM_LIBRARY_MINOR_VERSION
SODIUM_CRYPTO_AEAD_AES256GCM_KEYBYTES
SODIUM_CRYPTO_AEAD_AES256GCM_NSECBYTES
SODIUM_CRYPTO_AEAD_AES256GCM_NPUBBYTES
SODIUM_CRYPTO_AEAD_AES256GCM_ABYTES
SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_KEYBYTES
SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_NSECBYTES
SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_NPUBBYTES
SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_ABYTES
SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_IETF_KEYBYTES
SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_IETF_NSECBYTES
SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_IETF_NPUBBYTES
SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_IETF_ABYTES
SODIUM_CRYPTO_AUTH_BYTES
SODIUM_CRYPTO_AUTH_KEYBYTES
SODIUM_CRYPTO_BOX_SEALBYTES
SODIUM_CRYPTO_BOX_SECRETKEYBYTES
SODIUM_CRYPTO_BOX_PUBLICKEYBYTES
SODIUM_CRYPTO_BOX_KEYPAIRBYTES
SODIUM_CRYPTO_BOX_MACBYTES
SODIUM_CRYPTO_BOX_NONCEBYTES
SODIUM_CRYPTO_BOX_SEEDBYTES
SODIUM_CRYPTO_KDF_BYTES_MIN
SODIUM_CRYPTO_KDF_BYTES_MAX
SODIUM_CRYPTO_KDF_CONTEXTBYTES
SODIUM_CRYPTO_KDF_KEYBYTES
SODIUM_CRYPTO_KX_SEEDBYTES
SODIUM_CRYPTO_KX_SESSIONKEYBYTES
SODIUM_CRYPTO_KX_PUBLICKEYBYTES
SODIUM_CRYPTO_KX_SECRETKEYBYTES
SODIUM_CRYPTO_KX_KEYPAIRBYTES
SODIUM_CRYPTO_GENERICHASH_BYTES
SODIUM_CRYPTO_GENERICHASH_BYTES_MIN
SODIUM_CRYPTO_GENERICHASH_BYTES_MAX
SODIUM_CRYPTO_GENERICHASH_KEYBYTES
SODIUM_CRYPTO_GENERICHASH_KEYBYTES_MIN
SODIUM_CRYPTO_GENERICHASH_KEYBYTES_MAX
SODIUM_CRYPTO_PWHASH_ALG_ARGON2I13
SODIUM_CRYPTO_PWHASH_ALG_DEFAULT
SODIUM_CRYPTO_PWHASH_SALTBYTES
SODIUM_CRYPTO_PWHASH_STRPREFIX
SODIUM_CRYPTO_PWHASH_OPSLIMIT_INTERACTIVE
SODIUM_CRYPTO_PWHASH_MEMLIMIT_INTERACTIVE
SODIUM_CRYPTO_PWHASH_OPSLIMIT_MODERATE
SODIUM_CRYPTO_PWHASH_MEMLIMIT_MODERATE
SODIUM_CRYPTO_PWHASH_OPSLIMIT_SENSITIVE
SODIUM_CRYPTO_PWHASH_MEMLIMIT_SENSITIVE
SODIUM_CRYPTO_PWHASH_SCRYPTSALSA208SHA256_SALTBYTES
SODIUM_CRYPTO_PWHASH_SCRYPTSALSA208SHA256_STRPREFIX
SODIUM_CRYPTO_PWHASH_SCRYPTSALSA208SHA256_OPSLIMIT_INTERACTIVE
SODIUM_CRYPTO_PWHASH_SCRYPTSALSA208SHA256_MEMLIMIT_INTERACTIVE
SODIUM_CRYPTO_PWHASH_SCRYPTSALSA208SHA256_OPSLIMIT_SENSITIVE
SODIUM_CRYPTO_PWHASH_SCRYPTSALSA208SHA256_MEMLIMIT_SENSITIVE
SODIUM_CRYPTO_SCALARMULT_BYTES
SODIUM_CRYPTO_SCALARMULT_SCALARBYTES
SODIUM_CRYPTO_SHORTHASH_BYTES
SODIUM_CRYPTO_SHORTHASH_KEYBYTES
SODIUM_CRYPTO_SECRETBOX_KEYBYTES
SODIUM_CRYPTO_SECRETBOX_MACBYTES
SODIUM_CRYPTO_SECRETBOX_NONCEBYTES
SODIUM_CRYPTO_SIGN_BYTES
SODIUM_CRYPTO_SIGN_SEEDBYTES
SODIUM_CRYPTO_SIGN_PUBLICKEYBYTES
SODIUM_CRYPTO_SIGN_SECRETKEYBYTES
SODIUM_CRYPTO_SIGN_KEYPAIRBYTES
SODIUM_CRYPTO_STREAM_NONCEBYTES
SODIUM_CRYPTO_STREAM_KEYBYTES
Zip
ZipArchive::EM_NONE
ZipArchive::EM_AES_128
ZipArchive::EM_AES_192
ZipArchive::EM_AES_256
Backward incompatible changes
Prevent number_format from returning negative zero
Previously, it was possible for the number_format
   function to return -0. Whilst this is perfectly valid
   according to the IEEE 754 floating point specification, this oddity was not
   desirable for displaying formatted numbers in a human-readable form.
Convert numeric keys in object and array casts
Numeric keys are now better handled when casting arrays to objects and
   objects to arrays (either from explicit casting or by
   settype).
This means that integer (or stringy integer) keys from arrays being casted
   to objects are now accessible:
And integer (or stringy integer) keys from objects being casted to arrays
   are now accessible:
Disallow passing  to get_class
Previously, passing  to the get_class function
   would output the name of the enclosing class. This behaviour has now been
   removed, where an E_WARNING will be output instead. To
   achieve the same behaviour as before, the argument should simply be omitted.
Warn when counting non-countable types
An E_WARNING will now be emitted when attempting to
   count non-countable types (this includes the
   sizeof alias function).
Move ext/hash from resources to objects
As part of the long-term migration away from resources, the Hash
   extension has been updated to use objects instead of resources. The change should be
   seamless for PHP developers, except for where
   is_resource checks have been made (which will need
   updating to is_object instead).
Improve SSL/TLS defaults
The following changes to the defaults have been made:
tls:// now defaults to TLSv1.0 or TLSv1.1 or TLSv1.2
ssl:// an alias of tls://
STREAM_CRYPTO_METHOD_TLS_* constants default to TLSv1.0
     or TLSv1.1 + TLSv1.2, instead of TLSv1.0 only
gettype return value on closed resources
Previously, using gettype on a closed resource would
   return a string of "unknown type". Now, a string of
   "resource (closed)" will be returned.
is_object and __PHP_Incomplete_Class
Previously, using is_object on the
   __PHP_Incomplete_Class class would return .
   Now,  will be returned.
Promote the error level of undefined constants
Unqualified references to undefined constants will now generate an
   E_WARNING (instead of an E_NOTICE).
   In the next major version of PHP, they will generate
   Error exceptions.
Windows support
The officially supported, minimum Windows versions are now Windows 7/Server
   2008 R2.
Checks on default property values of traits
Compatibility checks upon default trait property values will no longer
   perform casting.
object for class names
The object name was previously soft-reserved in PHP 7.0.
   This is now hard-reserved, prohibiting it from being used as a class, trait,
   or interface name.
NetWare support
Support for NetWare has now been removed.
array_unique with SORT_STRING
While array_unique with SORT_STRING
   formerly copied the array and removed non-unique elements (without packing
   the array afterwards), now a new array is built by adding the
   unique elements. This can result in different numeric indexes.
bcmod changes with floats
The bcmod function no longer truncates fractional
   numbers to integers. As such, its behavior now follows
   fmod, rather than the % operator.
   For example bcmod('4', '3.5') now returns
   0.5 instead of 1.
Hashing functions and non-cryptographic hashes
The hash_hmac, hash_hmac_file,
   hash_pbkdf2, and hash_init (with
   HASH_HMAC) functions no longer accept non-cryptographic
   hashes.
json_decode function options
The json_decode function option,
   JSON_OBJECT_AS_ARRAY, is now used if the second
   parameter (assoc) is . Previously,
   JSON_OBJECT_AS_ARRAY was always ignored.
rand and mt_rand output
Sequences generated by rand and
   mt_rand for a specific seed may differ from PHP 7.1 on
   64-bit machines (due to the fixing of a modulo bias bug in the
   implementation).
Removal of sql.safe_mode ini setting
The sql.safe_mode ini setting has now been removed.
Changes to date_parse and date_parse_from_format
The zone element of the array returned by date_parse and
   date_parse_from_format represents seconds instead of
   minutes now, and its sign is inverted. For instance -120
   is now 7200.
Incoming Cookies
As of PHP 7.2.34, the names of incoming cookies are no
   longer url-decoded for security reasons.
Other changes
Moving of utf8_encode and utf8_decode
The utf8_encode and utf8_decode
   functions have now been moved to the standard extension as string functions, whereas before 
   the XML extension was required for them to be available.
Changes to mail and mb_send_mail
The $additional_headers parameter of mail and
   mb_send_mail now also accepts an array
   instead of a string.
LMDB support
The DBA extension now has support for LMDB.
Changes to the PHP build system
Unix: Autoconf 2.64 or greater is now required to build PHP.
Unix: --with-pdo-oci configure argument no longer needs 
     the version number of the Oracle Instant Client.
Unix: --enable-gd-native-ttf configure argument has been 
     removed. This was not used since PHP 5.5.0.
Windows: --with-config-profile configure argument has been 
     added. This can be used to save specific configures, much like the magical 
     config.nice.bat file.
Changes to GD
imageantialias is now also available if compiled with
     a system libgd.
imagegd stores truecolor images as real truecolor
     images. Formerly, they have been converted to palette.
Moving MCrypt to PECL
The MCrypt extension has now been moved
   out of the core to PECL. Given the mcrypt library has not seen any updates
   since 2007, its usage is highly discouraged. Instead, either the
   OpenSSL or Sodium
   extension should be used.
session_module_name
Passing "user" to session_module_name
   now raises an error of level E_RECOVERABLE_ERROR. Formerly,
   this has been silently ignored.
New features
New object type
A new type, object, has been introduced that can be used for
   (contravariant) parameter typing and (covariant) return typing of any
   objects.
Extension loading by name
Shared extensions no longer require their file extension
   (.so for Unix or .dll for Windows) to
   be specified. This is enabled in the php.ini file, as well as in the
   dl function.
Abstract method overriding
Abstract methods can now be overridden when an abstract class extends
   another abstract class.
Sodium is now a core extension
The modern Sodium cryptography library has now become a core extension in PHP.
For a complete function reference, see the Sodium
   chapter.
Password hashing with Argon2
Argon2 has been added to the password hashing API, 
   where the following constants have been exposed:
PASSWORD_ARGON2I
PASSWORD_ARGON2_DEFAULT_MEMORY_COST
PASSWORD_ARGON2_DEFAULT_TIME_COST
PASSWORD_ARGON2_DEFAULT_THREADS
Extended string types for PDO
PDO's string type has been extended to support the national character type
   when emulating prepares. This has been done with the following constants:
PDO::PARAM_STR_NATL
PDO::PARAM_STR_CHAR
PDO::ATTR_DEFAULT_STR_PARAM
These constants are utilised by bitwise OR'ing them with
   PDO::PARAM_STR:
Additional emulated prepares debugging information for PDO
The PDOStatement::debugDumpParams method has been
   updated to include the SQL being sent to the DB, where the full, raw query
   (including the replaced placeholders with their bounded values) will be
   shown. This has been added to aid with debugging emulated prepares (and so
   it will only be available when emulated prepares are turned on).
Support for extended operations in LDAP
Support for EXOP has been added to the LDAP extension. This has been done by
   exposing the following functions and constants:
ldap_parse_exop
ldap_exop
ldap_exop_passwd
ldap_exop_whoami
LDAP_EXOP_START_TLS
LDAP_EXOP_MODIFY_PASSWD
LDAP_EXOP_REFRESH
LDAP_EXOP_WHO_AM_I
LDAP_EXOP_TURN
Address Information additions to the Sockets extension
The sockets extension now has the ability to lookup address information, as
   well as connect to it, bind to it, and explain it. The following four
   functions have been added for this:
socket_addrinfo_lookup
socket_addrinfo_connect
socket_addrinfo_bind
socket_addrinfo_explain
Parameter type widening
Parameter types from overridden methods and from interface implementations
   may now be omitted. This is still in compliance with LSP, since parameters
   types are contravariant.
Allow a trailing comma for grouped namespaces
A trailing comma can now be added to the group-use syntax introduced in
   PHP 7.0.
proc_nice support on Windows
The proc_nice function is now supported on Windows.
pack and unpack endian support
The pack and unpack functions now
   support float and double in both little and big endian.
Enhancements to the EXIF extension
The EXIF extension has been updated to support a much larger range of formats. This 
   means that their format specific tags are now properly translated when parsing images 
   with the exif_read_data function. The following new formats are 
   now supported:
Samsung
DJI
Panasonic
Sony
Pentax
Minolta
Sigma/Foveon
AGFA
Kyocera
Ricoh
Epson
The EXIF functions exif_read_data and exif_thumbnail 
   now support passing streams as their first argument.
New features in PCRE
The J modifier for setting PCRE_DUPNAMES has been added.
SQLite3 allows writing BLOBs
SQLite3::openBlob now allows to open BLOB fields in
   write mode; formerly only read mode was supported.
Oracle OCI8 Transparent Application Failover Callbacks
Support for Oracle Database Transparent Application Failover (TAF) callbacks
   has been added. TAF allows PHP OCI8 applications to
   automatically reconnect to a preconfigured database when a connection
   is broken.  The new TAF callback support allows PHP applications to
   monitor and control reconnection during failover.
Enhancements to the ZIP extension
Read and write support for encrypted archives has been added (requires libzip 1.2.0).
The ZipArchive class now implements the Countable 
   interface.
The zip:// stream now accepts a 'password' context option.
Deprecated features in PHP 7.2.x
Unquoted strings
Unquoted strings that are non-existent global constants are taken to be
   strings of themselves. This behaviour used to emit an
   E_NOTICE, but will now emit an
   E_WARNING. In the next major version of PHP, an
   Error exception will be thrown instead.
png2wbmp and jpeg2wbmp
The png2wbmp and jpeg2wbmp
   functions from the GD extension have now been deprecated and will be removed
   in the next major version of PHP.
INTL_IDNA_VARIANT_2003 variant
The Intl extension has deprecated the
   INTL_IDNA_VARIANT_2003 variant, which is currently
   being used as the default for idn_to_ascii and
   idn_to_utf8. PHP 7.4 will see these defaults changed to
   INTL_IDNA_VARIANT_UTS46, and the next major version of
   PHP will remove INTL_IDNA_VARIANT_2003 altogether.
__autoload method
The __autoload method has been deprecated because it is
   inferior to spl_autoload_register (due to it not being
   able to chain autoloaders), and there is no interoperability between the two
   autoloading styles.
track_errors ini setting and $php_errormsg variable
When the track_errors ini setting is enabled, a
   $php_errormsg variable is created in the local scope when
   a non-fatal error occurs. Given that the preferred way of retrieving such
   error information is by using error_get_last, this
   feature has been deprecated.
create_function function
Given the security issues of this function (being a thin wrapper around
   eval), this dated function has now been deprecated.
   The preferred alternative is to use anonymous functions.
mbstring.func_overload ini setting
Given the interoperability problems of string-based functions being used in
   environments with this setting enabled, it has now been deprecated.
(unset) cast
Casting any expression to this type will always result in , and so
   this superfluous casting type has now been deprecated.
parse_str without a second argument
Without the second argument to parse_str, the query
   string parameters would populate the local symbol table.
   Given the security implications of this, using
   parse_str without a second argument has now been
   deprecated. The function should always be used with two arguments, as the
   second argument causes the query string to be parsed into an array.
gmp_random function
This function generates a random number based upon a range that is
   calculated by an unexposed, platform-specific limb size. Because of this,
   the function has now been deprecated. The preferred way of generating a
   random number using the GMP extension is by
   gmp_random_bits and
   gmp_random_range.
each function
This function is far slower at iteration than a normal
   foreach, and causes implementation issues for some
   language changes. It has therefore been deprecated.
assert with a string argument
Using assert with a string argument required the string
   to be eval'ed. Given the potential for remote code
   execution, using assert with a string argument has now
   been deprecated in favour of using boolean expressions.
$errcontext argument of error handlers
The $errcontext argument contains all local variables of
   the error site. Given its rare usage, and the problems it causes with
   internal optimisations, it has now been deprecated.
   Instead, a debugger should be used to retrieve
   information on local variables at the error site.
read_exif_data function
The read_exif_data alias has been deprecated.
   The exif_read_data function should be used instead.
Windows Support
PHP Core
More POSIX Conforming File Deletion
File descriptors are opened in shared read/write/delete mode by default.
    This effectively maps the POSIX semantics and allows to
    delete files with handles in use. It is not 100% same, some platform
    differences still persist. After the deletion, the filename entry is
    blocked, until all the opened handles to it are closed.
New Functions
PHP Core
array_key_first
array_key_last
gc_status
hrtime
is_countable
net_get_interfaces
FastCGI Process Manager
fpm_get_status
Date and Time
DateTime::createFromImmutable
GNU Multiple Precision
gmp_binomial
gmp_kronecker
gmp_lcm
gmp_perfect_power
Internationalization Functions
Normalizer::getRawDecomposition
normalizer_get_raw_decomposition
Spoofchecker::setRestrictionLevel
Lightweight Directory Access Protocol
ldap_add_ext
ldap_bind_ext
ldap_delete_ext
ldap_exop_refresh
ldap_mod_add_ext
ldap_mod_replace_ext
ldap_mod_del_ext
ldap_rename_ext
OpenSSL
openssl_pkey_derive
Sockets
socket_wsaprotocol_info_export
socket_wsaprotocol_info_import
socket_wsaprotocol_info_release
New Global Constants
PHP Core
PASSWORD_ARGON2ID
Client URL Library
CURLAUTH_BEARER
CURLAUTH_GSSAPI
CURLE_WEIRD_SERVER_REPLY
CURLINFO_APPCONNECT_TIME_T
CURLINFO_CONNECT_TIME_T
CURLINFO_CONTENT_LENGTH_DOWNLOAD_T
CURLINFO_CONTENT_LENGTH_UPLOAD_T
CURLINFO_FILETIME_T
CURLINFO_HTTP_VERSION
CURLINFO_NAMELOOKUP_TIME_T
CURLINFO_PRETRANSFER_TIME_T
CURLINFO_PROTOCOL
CURLINFO_PROXY_SSL_VERIFYRESULT
CURLINFO_REDIRECT_TIME_T
CURLINFO_SCHEME
CURLINFO_SIZE_DOWNLOAD_T
CURLINFO_SIZE_UPLOAD_T
CURLINFO_SPEED_DOWNLOAD_T
CURLINFO_SPEED_UPLOAD_T
CURLINFO_STARTTRANSFER_TIME_T
CURLINFO_TOTAL_TIME_T
CURL_LOCK_DATA_CONNECT
CURL_LOCK_DATA_PSL
CURL_MAX_READ_SIZE
CURLOPT_ABSTRACT_UNIX_SOCKET
CURLOPT_DISALLOW_USERNAME_IN_URL
CURLOPT_DNS_SHUFFLE_ADDRESSES
CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS
CURLOPT_HAPROXYPROTOCOL
CURLOPT_KEEP_SENDING_ON_ERROR
CURLOPT_PRE_PROXY
CURLOPT_PROXY_CAINFO
CURLOPT_PROXY_CAPATH
CURLOPT_PROXY_CRLFILE
CURLOPT_PROXY_KEYPASSWD
CURLOPT_PROXY_PINNEDPUBLICKEY
CURLOPT_PROXY_SSLCERT
CURLOPT_PROXY_SSLCERTTYPE
CURLOPT_PROXY_SSL_CIPHER_LIST
CURLOPT_PROXY_SSLKEY
CURLOPT_PROXY_SSLKEYTYPE
CURLOPT_PROXY_SSL_OPTIONS
CURLOPT_PROXY_SSL_VERIFYHOST
CURLOPT_PROXY_SSL_VERIFYPEER
CURLOPT_PROXY_SSLVERSION
CURLOPT_PROXY_TLS13_CIPHERS
CURLOPT_PROXY_TLSAUTH_PASSWORD
CURLOPT_PROXY_TLSAUTH_TYPE
CURLOPT_PROXY_TLSAUTH_USERNAME
CURLOPT_REQUEST_TARGET
CURLOPT_SOCKS5_AUTH
CURLOPT_SSH_COMPRESSION
CURLOPT_SUPPRESS_CONNECT_HEADERS
CURLOPT_TIMEVALUE_LARGE
CURLOPT_TLS13_CIPHERS
CURLPROXY_HTTPS
CURLSSH_AUTH_GSSAPI
CURL_SSLVERSION_MAX_DEFAULT
CURL_SSLVERSION_MAX_NONE
CURL_SSLVERSION_MAX_TLSv1_0
CURL_SSLVERSION_MAX_TLSv1_1
CURL_SSLVERSION_MAX_TLSv1_2
CURL_SSLVERSION_MAX_TLSv1_3
CURL_SSLVERSION_TLSv1_3
CURL_VERSION_ALTSVC (as of PHP 7.3.6)
CURL_VERSION_ASYNCHDNS
CURL_VERSION_BROTLI
CURL_VERSION_CONV
CURL_VERSION_CURLDEBUG (as of PHP 7.3.6)
CURL_VERSION_DEBUG
CURL_VERSION_GSSAPI
CURL_VERSION_GSSNEGOTIATE
CURL_VERSION_HTTPS_PROXY
CURL_VERSION_IDN
CURL_VERSION_LARGEFILE
CURL_VERSION_MULTI_SSL
CURL_VERSION_NTLM
CURL_VERSION_NTLM_WB
CURL_VERSION_PSL (as of PHP 7.3.6)
CURL_VERSION_SPNEGO
CURL_VERSION_SSPI
CURL_VERSION_TLSAUTH_SRP
Data Filtering
FILTER_SANITIZE_ADD_SLASHES
JavaScript Object Notation
JSON_THROW_ON_ERROR
Lightweight Directory Access Protocol
LDAP_CONTROL_ASSERT
LDAP_CONTROL_MANAGEDSAIT
LDAP_CONTROL_PROXY_AUTHZ
LDAP_CONTROL_SUBENTRIES
LDAP_CONTROL_VALUESRETURNFILTER
LDAP_CONTROL_PRE_READ
LDAP_CONTROL_POST_READ
LDAP_CONTROL_SORTREQUEST
LDAP_CONTROL_SORTRESPONSE
LDAP_CONTROL_PAGEDRESULTS
LDAP_CONTROL_AUTHZID_REQUEST
LDAP_CONTROL_AUTHZID_RESPONSE
LDAP_CONTROL_SYNC
LDAP_CONTROL_SYNC_STATE
LDAP_CONTROL_SYNC_DONE
LDAP_CONTROL_DONTUSECOPY
LDAP_CONTROL_PASSWORDPOLICYREQUEST
LDAP_CONTROL_PASSWORDPOLICYRESPONSE
LDAP_CONTROL_X_INCREMENTAL_VALUES
LDAP_CONTROL_X_DOMAIN_SCOPE
LDAP_CONTROL_X_PERMISSIVE_MODIFY
LDAP_CONTROL_X_SEARCH_OPTIONS
LDAP_CONTROL_X_TREE_DELETE
LDAP_CONTROL_X_EXTENDED_DN
LDAP_CONTROL_VLVREQUEST
LDAP_CONTROL_VLVRESPONSE
Multibyte String
MB_CASE_FOLD
MB_CASE_LOWER_SIMPLE
MB_CASE_UPPER_SIMPLE
MB_CASE_TITLE_SIMPLE
MB_CASE_FOLD_SIMPLE
OpenSSL
STREAM_CRYPTO_PROTO_SSLv3
STREAM_CRYPTO_PROTO_TLSv1_0
STREAM_CRYPTO_PROTO_TLSv1_1
STREAM_CRYPTO_PROTO_TLSv1_2
PostgreSQL
PGSQL_DIAG_SCHEMA_NAME
PGSQL_DIAG_TABLE_NAME
PGSQL_DIAG_COLUMN_NAME
PGSQL_DIAG_DATATYPE_NAME
PGSQL_DIAG_CONSTRAINT_NAME
PGSQL_DIAG_SEVERITY_NONLOCALIZED
Backward Incompatible Changes
PHP Core
Heredoc/Nowdoc Ending Label Interpretation
Due to the introduction of flexible heredoc/nowdoc
    syntax, doc strings that contain the ending label inside their body
    may cause syntax errors or change in interpretation. For example in:
    
     

<?php
$str = <<<FOO
abcdefg
   FOO
FOO;
?>

     
    
    the indented occurrence of FOO did not previously have any
    special meaning. Now it will be interpreted as the end of the heredoc string
    and the following FOO; will cause a syntax error. This issue can
    always be resolved by choosing an ending label that does not occur within the
    contents of the string.
Continue Targeting Switch issues Warning
continue statements targeting switch
    control flow structures will now generate a warning. In PHP such
    continue statements are equivalent to
    break, while they behave as continue 2
    in other languages.
    
     

<?php
while ($foo) {
    switch ($bar) {
      case "baz":
         continue;
         // Warning: "continue" targeting switch is equivalent to
         //          "break". Did you mean to use "continue 2"?
   }
}
?>
Strict Interpretation of Integer String Keys on ArrayAccess
Array accesses of type $obj["123"], where
    $obj implements ArrayAccess and
    "123" is an integer string literal will no
    longer result in an implicit conversion to integer, i.e.,
    $obj->offsetGet("123") will be called instead of
    $obj->offsetGet(123). This matches existing behavior for
    non-literals. The behavior of arrays is not affected in any way, they
    continue to implicitly convert integral string keys to integers.
Static Properties no longer separated by Reference Assignment
In PHP, static properties are shared between inheriting classes, unless the
    static property is explicitly overridden in a child class. However, due to an
    implementation artifact it was possible to separate the static properties by
    assigning a reference. This loophole has been fixed.
    
     

<?php
class Test {
    public static $x = 0;
}
class Test2 extends Test { }

Test2::$x = &$x;
$x = 1;

var_dump(Test::$x, Test2::$x);
// Previously: int(0), int(1)
// Now:        int(1), int(1)
?>
References returned by Array and Property Accesses are immediately unwrapped
References returned by array and property accesses are now unwrapped as part
    of the access. This means that it is no longer possible to modify the
    reference between the access and the use of the accessed value:
    
     

<?php
$arr = [1];
$ref =& $arr[0];
var_dump($arr[0] + ($arr[0] = 2));
// Previously: int(4), Now: int(3)
?>

     
    
    This makes the behavior of references and non-references consistent. Please
    note that reading and writing a value inside a single expression remains
    undefined behavior and may change again in the future.
Argument Unpacking of Traversables with non-Integer Keys no longer supported
Argument unpacking stopped working with Traversables
    with non-integer keys. The following code worked in PHP 5.6-7.2 by accident.
    
     

<?php
function foo(...$args) {
    var_dump($args);
}
function gen() {
    yield 1.23 => 123;
}
foo(...gen());
?>
Miscellaneous
The ext_skel utility has been completely redesigned with
    new options and some old options removed. This is now written in PHP and has
    no external dependencies.
Support for BeOS has been dropped.
Exceptions thrown due to automatic conversion of warnings into exceptions in
    EH_THROW mode (e.g. some DateTime
    exceptions) no longer populate error_get_last state. As
    such, they now work the same way as manually thrown exceptions.
TypeError now reports wrong types as
    int and bool instead of
    integer and boolean, respectively.
Undefined variables passed to compact will now be
    reported as a notice.
getimagesize and related functions now report the mime
    type of BMP images as image/bmp instead of
    image/x-ms-bmp, since the former has been registered with
    the IANA (see RFC 7903).
stream_socket_get_name will now return IPv6 addresses
    wrapped in brackets. For example "[::1]:1337" will be
    returned instead of "::1:1337".
BCMath Arbitrary Precision Mathematics
All warnings thrown by BCMath functions are
   now using PHP's error handling. Formerly some warnings have directly been
   written to stderr.
bcmul and bcpow now return numbers
   with the requested scale. Formerly, the returned numbers may have omitted
   trailing decimal zeroes.
IMAP, POP3 and NNTP
rsh/ssh logins are disabled by default.
   Use imap.enable_insecure_rsh if you
   want to enable them. Note that the IMAP library does not filter mailbox names
   before passing them to the rsh/ssh
   command, thus passing untrusted data to this function with
   rsh/ssh enabled is insecure.
Multibyte String
Due to added support for named captures, mb_ereg_*()
    patterns using named captures will behave differently. In particular named
    captures will be part of matches and mb_ereg_replace
    will interpret additional syntax. See Named
    Captures for more information.
MySQL Improved Extension
Prepared statements now properly report the fractional seconds for
   DATETIME, TIME and
   TIMESTAMP columns with decimals specifier (e.g.
   TIMESTAMP(6) when using microseconds). Formerly, the
   fractional seconds part was simply omitted from the returned values.
MySQL Functions (PDO_MYSQL)
Prepared statements now properly report the fractional seconds for
   DATETIME, TIME and
   TIMESTAMP columns with decimals specifier (e.g.
   TIMESTAMP(6) when using microseconds). Formerly, the
   fractional seconds part was simply omitted from the returned values. Please
   note that this only affects the usage of PDO_MYSQL with emulated prepares turned off
   (e.g. using the native preparation functionality). Statements using
   connections having PDO::ATTR_EMULATE_PREPARES=
   (which is the default) were not affected by the bug fixed and have already
   been getting the proper fractional seconds values from the engine.
Reflection
Reflection export to string now uses
   int and bool instead of
   integer and boolean, respectively.
Standard PHP Library (SPL)
If an SPL autoloader throws an exception,
   following autoloaders will not be executed. Previously all autoloaders were
   executed and exceptions were chained.
SimpleXML
Mathematic operations involving SimpleXML objects will now treat the text as
   an int or float, whichever is more appropriate.
   Previously values were treated as ints unconditionally.
Incoming Cookies
As of PHP 7.3.23, the names of incoming cookies are no
   longer url-decoded for security reasons.
Other Changes
PHP Core
Set(raw)cookie accepts $option Argument
setcookie and setrawcookie now also
    support the following signature:
    
     boolsetcookie
     stringname
     stringvalue""
     arrayoptions[]
    
    where $options is an associative array which may have
    any of the keys "expires", "path",
    "domain", "secure",
    "httponly" and "samesite".
New Syslog ini Directives
The following ini Directives have been added to customize logging, if
    error_log is set to
    syslog:
    
     
      syslog.facility
      
       
        Specifies what type of program is logging the message.
       
      
     
     
      syslog.filter
      
       
        Specifies the filter type to filter the logged messages, with the
        supported filter types - all,
        no-ctrl and ascii.
        Starting with PHP 7.3.8, raw is also available, 
        restoring the way syslog behaved in previous PHP versions.
        This filter will also affect calls to syslog.
       
      
     
     
      syslog.ident
      
       
        Specifies the ident string which is prepended to every message.
Specifies what type of program is logging the message.
Specifies the filter type to filter the logged messages, with the
        supported filter types - all,
        no-ctrl and ascii.
        Starting with PHP 7.3.8, raw is also available, 
        restoring the way syslog behaved in previous PHP versions.
        This filter will also affect calls to syslog.
Specifies the ident string which is prepended to every message.
Garbage Collection
The cyclic GC has been
    enhanced, which may result in considerable performance improvements.
Miscellaneous
var_export now exports stdClass
    objects as an array cast to an object ((object) array( ... )), rather
    than using the nonexistent method stdClass::__setState.
debug_zval_dump was changed to display recursive arrays
    and objects in the same way as var_dump. Now, it doesn't
    display them twice.
array_push and array_unshift can
    now also be called with a single argument, which is particularly convenient
    wrt. the spread operator.
Interactive PHP Debugger
The unused constants PHPDBG_FILE,
   PHPDBG_METHOD, PHPDBG_LINENO and
   PHPDBG_FUNC have been removed.
FastCGI Process Manager
The getallheaders function is now also available.
Client URL Library
libcurl ≥ 7.15.5 is now required.
Data Filtering
FILTER_VALIDATE_FLOAT now also supports a thousand
   option, which defines the set of allowed thousand separator chars.  The default
   ("',.") is fully backward compatible with former PHP versions.
FILTER_SANITIZE_ADD_SLASHES has been added as an alias of the
   magic_quotes filter (FILTER_SANITIZE_MAGIC_QUOTES).
   The magic_quotes filter is subject to removal in future versions of PHP.
FTP
The default transfer mode has been changed to binary.
Internationalization Functions
Normalizer::NONE is deprecated, when PHP is linked with
   ICU ≥ 56.
Introduced Normalizer::FORM_KC_CF as
   Normalizer::normalize argument for
   NFKC_Casefold normalization; available when linked with
   ICU ≥ 56.
JavaScript Object Notation
A new flag has been added, JSON_THROW_ON_ERROR, which
   can be used with json_decode or
   json_encode and causes these functions to throw the new
   JsonException upon an error, instead of setting the
   global error state that is retrieved with
   json_last_error and json_last_error_msg.
   JSON_PARTIAL_OUTPUT_ON_ERROR takes precedence over
   JSON_THROW_ON_ERROR.
Multibyte String
The configuration option --with-libmbfl is
   no longer available.
ODBC (Unified)
Support for ODBCRouter and Birdstep
   including the birdstep.max_links ini directive has been
   removed.
OPcache
The opcache.inherited_hack ini directive has been removed.
   The value has already been ignored since PHP 5.3.0.
OpenSSL
The min_proto_version and max_proto_version
   ssl stream options as well as related constants for possible TLS protocol values
   have been added.
Regular Expressions (Perl-Compatible)
The PCRE extension has been upgraded to
   PCRE2, which may cause minor behavioral changes (for instance, character
   ranges in classes are now more strictly interpreted), and augments the
   existing regular expression syntax.
preg_quote now also escapes the '#'
   character.
Microsoft SQL Server and Sybase Functions (PDO_DBLIB)
The attribute PDO::DBLIB_ATTR_SKIP_EMPTY_ROWSETS to enable automatic
   skipping of empty rowsets has been added.
The PDO::DBLIB_ATTR_TDS_VERSION attribute which exposes
   the TDS version has been added.
DATETIME2 columns are now treated like DATETIME columns.
SQLite Functions (PDO_SQLITE)
SQLite3 databases can now be opened in read-only mode by setting the
   new PDO::SQLITE_ATTR_OPEN_FLAGS attribute to
   PDO::SQLITE_OPEN_READONLY.
Session Handling
session_set_cookie_params now also supports the
   following signature:
   
    boolsession_set_cookie_params
    arrayoptions
   
   where $options is an associative array which may have
   any of the keys "lifetime", "path",
   "domain", "secure",
   "httponly" and "samesite". Accordingly,
   the return value of session_get_cookie_params now also
   has an element with the key "samesite".
   Furthermore, the new session.cookie_samesite ini option to
   set the default of the SameSite directive for cookies has been added. It
   defaults to "" (empty string), so no SameSite directive is
   set. Can be set to "Lax" or "Strict",
   which sets the respective SameSite directive.
Tidy
Building against tidyp is now also
   supported transparently. Since tidyp offers no API to get the release date,
   tidy_get_release and tidy::getRelease
   return 'unknown' in this case.
XML Parser
The return value of the xml_set_external_entity_ref_handler
   callback is no longer ignored if the extension has been built against libxml.
   Formerly, the return value has been ignored, and parsing did never stop.
Zip
Building against the bundled libzip is discouraged, but still possible by
   adding --without-libzip to the configuration.
Zlib Compression
The zlib/level context option for the compress.zlib wrapper to facilitate
   setting the desired compression level has been added.
New Features
PHP Core
More Flexible Heredoc and Nowdoc Syntax
The closing marker for doc strings is no longer required to be followed by a
    semicolon or newline. Additionally the closing marker may be indented, in
    which case the indentation will be stripped from all lines in the doc string.
Array Destructuring supports Reference Assignments
Array destructuring now supports reference assignments using the syntax
    [&$a, [$b, &$c]] = $d. The same is also supported
    for list.
Instanceof Operator accepts Literals
instanceof now allows literals as the first operand, in
    which case the result is always .
CompileError Exception instead of some Compilation Errors
A new CompileError exception has been added, from
    which ParseError inherits. A small number of
    compilation errors will now throw a CompileError
    instead of generating a fatal error. Currently this only affects compilation
    errors that may be thrown by token_get_all in
    TOKEN_PARSE mode, but more errors may be converted in
    the future.
Trailing Commas are allowed in Calls
Trailing commas in function and method calls are now allowed.
Argon2id Support
The --with-password-argon2[=dir] configure
    argument now provides support for both Argon2i and Argon2id hashes in the
    password_hash, password_verify,
    password_get_info, and
    password_needs_rehash functions. Passwords may be hashed
    and verified using the PASSWORD_ARGON2ID constant.
    Support for both Argon2i and Argon2id in the password_*
    functions now requires PHP be linked against libargon2 reference library ≥
    20161029.
FastCGI Process Manager
New options have been added to customize the FPM logging:
   
    
     log_limit
     
      
       This global option can be used for setting the log limit for the logged
       line which allows to log messages longer than 1024 characters without
       wrapping. It also fixes various wrapping issues.
      
     
    
    
     log_buffering
     
      
       This global option allows an experimental logging without extra buffering.
      
     
    
    
     decorate_workers_output
     
      
       This pool option allows to disable the output decoration for workers
       output when catch_workers_output is enabled.
This global option can be used for setting the log limit for the logged
       line which allows to log messages longer than 1024 characters without
       wrapping. It also fixes various wrapping issues.
This global option allows an experimental logging without extra buffering.
This pool option allows to disable the output decoration for workers
       output when catch_workers_output is enabled.
BC Math Functions
bcscale can now also be used as getter to retrieve the
   current scale in use.
Lightweight Directory Access Protocol
Full support for LDAP Controls has been added to the LDAP querying functions and
   ldap_parse_result:
   
    
     
      A $controls parameter to send controls to the
      server in ldap_add,
      ldap_mod_replace, ldap_mod_add,
      ldap_mod_del, ldap_rename,
      ldap_compare, ldap_delete,
      ldap_modify_batch,
      ldap_search, ldap_list and
      ldap_read has been added.
     
    
    
     
      The out parameter $controls to get controls from the server in
      ldap_parse_result has been added.
     
    
    
     
      Support for LDAP_OPT_SERVER_CONTROLS and
      LDAP_OPT_CLIENT_CONTROLS in
      ldap_get_option and
      ldap_set_option has been fixed.
A $controls parameter to send controls to the
      server in ldap_add,
      ldap_mod_replace, ldap_mod_add,
      ldap_mod_del, ldap_rename,
      ldap_compare, ldap_delete,
      ldap_modify_batch,
      ldap_search, ldap_list and
      ldap_read has been added.
The out parameter $controls to get controls from the server in
      ldap_parse_result has been added.
Support for LDAP_OPT_SERVER_CONTROLS and
      LDAP_OPT_CLIENT_CONTROLS in
      ldap_get_option and
      ldap_set_option has been fixed.
Multibyte String Functions
Full Case-Mapping and Case-Folding Support
Support for full case-mapping and case-folding has been added. Unlike simple
    case-mapping, full case-mapping may change the length of the string. For
    example:
    
     

<?php
mb_strtoupper("Straße");
// Produces STRAßE on PHP 7.2
// Produces STRASSE on PHP 7.3
?>

     
    
    The different casing mapping and folding modes are available through
    mb_convert_case:
    
     
      
       MB_CASE_LOWER (used by mb_strtolower)
      
     
     
      
       MB_CASE_UPPER (used by mb_strtoupper)
      
      
     
      
       MB_CASE_TITLE
      
      
     
      
       MB_CASE_FOLD
      
      
     
      
       MB_CASE_LOWER_SIMPLE
      
      
     
      
       MB_CASE_UPPER_SIMPLE
      
      
     
      
       MB_CASE_TITLE_SIMPLE
      
      
     
      
       MB_CASE_FOLD_SIMPLE (used by case-insensitive operations)
      
      
    
    Only unconditional, language agnostic full case-mapping is performed.
MB_CASE_LOWER (used by mb_strtolower)
MB_CASE_UPPER (used by mb_strtoupper)
MB_CASE_TITLE
MB_CASE_FOLD
MB_CASE_LOWER_SIMPLE
MB_CASE_UPPER_SIMPLE
MB_CASE_TITLE_SIMPLE
MB_CASE_FOLD_SIMPLE (used by case-insensitive operations)
Case-Insensitive String Operations use Case-Folding
Case-insensitive string operations now use case-folding instead of case-
    mapping during comparisons. This means that more characters will be
    considered (case insensitively) equal now.
MB_CASE_TITLE performs Title-Case Conversion
mb_convert_case with MB_CASE_TITLE
    now performs title-case conversion based on the Cased and CaseIgnorable
    derived Unicode properties. In particular this also improves handling of
    quotes and apostrophes.
Unicode 11 Support
The Multibyte String data tables have
    been updated for Unicode 11.
Long String Support
The Multibyte String Functions now
    correctly support strings larger than 2GB.
Performance Improvements
Performance of the Multibyte String
    extension has been significantly improved across the board. The largest
    improvements are in case conversion functions.
Named Captures Support
The mb_ereg_* functions now support named captures.
    Matching functions like mb_ereg will now return named
    captures both using their group number and their name, similar to PCRE:
    
     

<?php
mb_ereg('(?<word>\w+)', '国', $matches);
// => [0 => "国", 1 => "国", "word" => "国"];
?>

     
    
    Additionally, mb_ereg_replace now supports the
    \k and \k'' notations to reference named
    captures in the replacement string:
    
     

<?php
mb_ereg_replace('\s*(?<word>\w+)\s*', "_\k<word>_\k'word'_", ' foo ');
// => "_foo_foo_"
?>

     
    
    \k and \k'' can also be used for numbered
    references, which also works with group numbers greater than 9.
Readline
Support for the completion_append_character and
   completion_suppress_append options has been added to
   readline_info. These options are only available if PHP
   is linked against libreadline (rather than libedit).
Deprecated Features
PHP Core
Case-Insensitive Constants
The declaration of case-insensitive constants has been deprecated. Passing
     as the third argument to define will now generate a
    deprecation warning. The use of case-insensitive constants with a case that
    differs from the declaration is also deprecated.
Namespaced assert()
Declaring a function called assert() inside a namespace is
    deprecated. The assert function is subject to special
    handling by the engine, which may lead to inconsistent behavior when defining
    a namespaced function with the same name.
Searching Strings for non-string Needle
Passing a non-string needle to string search functions is deprecated. In the
    future the needle will be interpreted as a string instead of an ASCII
    codepoint. Depending on the intended behavior, you should either explicitly
    cast the needle to string or perform an explicit call to
    chr. The following functions are affected:
    
     
      strpos
     
     
      strrpos
     
     
      stripos
     
     
      strripos
     
     
      strstr
     
     
      strchr
     
     
      strrchr
     
     
      stristr
strpos
strrpos
stripos
strripos
strstr
strchr
strrchr
stristr
Strip-Tags Streaming
The fgetss function and the string.strip_tags stream filter have been
    deprecated. This also affects the
    SplFileObject::fgetss
    method and gzgetss function.
Data Filtering
The explicit usage of the constants
   FILTER_FLAG_SCHEME_REQUIRED and
   FILTER_FLAG_HOST_REQUIRED is now deprecated; both are
   implied for FILTER_VALIDATE_URL anyway.
Image Processing and GD
image2wbmp has been deprecated.
Internationalization Functions
Usage of the Normalizer::NONE form throws a deprecation
   warning, if PHP is linked with ICU ≥ 56.
Multibyte String
The following undocumented mbereg_*() aliases have been
   deprecated. Use the corresponding mb_ereg_*() variants
   instead.
   
    
     mbregex_encoding 
    
    
     mbereg 
    
    
     mberegi 
    
    
     mbereg_replace 
    
    
     mberegi_replace 
    
    
     mbsplit 
    
    
     mbereg_match 
    
    
     mbereg_search 
    
    
     mbereg_search_pos 
    
    
     mbereg_search_regs 
    
    
     mbereg_search_init 
    
    
     mbereg_search_getregs 
    
    
     mbereg_search_getpos 
    
    
     mbereg_search_setpos
mbregex_encoding
mbereg
mberegi
mbereg_replace
mberegi_replace
mbsplit
mbereg_match
mbereg_search
mbereg_search_pos
mbereg_search_regs
mbereg_search_init
mbereg_search_getregs
mbereg_search_getpos
mbereg_search_setpos
ODBC and DB2 Functions (PDO_ODBC)
The pdo_odbc.db2_instance_name
   ini setting has been formally deprecated. It is deprecated in the
   documentation as of PHP 5.1.1.
Windows Support
configure flags
configure now regards additional CFLAGS and LDFLAGS set as environment
   variables.
CTRL handling
CTRL
    C
   
   and
   
    CTRL
    BREAK
   
   on console can be caught by setting a handler function
   with sapi_windows_set_ctrl_handler.
proc_open on Windows can be passed a
   "create_process_group" option. It is required if the child
   process is supposed to handle CTRL events.
OPcache
OPcache now supports an arbitrary number of separate caches per user via the
   INI directive opcache.cache_id.
   All processes with the same cache ID and user share an OPcache instance.
stat
The stat implementation has been refactored.
An inode number is delivered and is based on the NTFS file index.
The device number is now based on the volume serial number.
Note that both values are derived from the system and provided as-is on 64-bit
   systems. On 32-bit systems, these values might overflow the 32-bit integer in
   PHP, so they're fake.
libsqlite3
libsqlite3 is no longer compiled statically into php_sqlite3.dll
   and php_pdo_sqlite.dll, but rather available as libsqlite3.dll.
   Refer to the installation instructions for SQLite3 and
   PDO_SQLITE, respectively.
New Classes and Interfaces
Reflection
ReflectionReference
New Functions
PHP Core
get_mangled_object_vars
password_algos
sapi_windows_set_ctrl_handler
GD
imagecreatefromtga
Multibyte String
mb_str_split
OpenSSL
openssl_x509_verify
Process Control
pcntl_unshare
SQLite3
SQLite3::backup
SQLite3Stmt::getSQL
Removed Extensions
These extensions have been moved to PECL and are no longer part of the PHP
  distribution. The PECL package versions of these extensions will be created
  according to user demand.
Firebird/Interbase
    - access to an InterBase and/or Firebird based database is still
    available with the PDO Firebird driver.
Recode
WDDX
New Global Constants
PHP Core
PHP_WINDOWS_EVENT_CTRL_C
PHP_WINDOWS_EVENT_CTRL_BREAK
Multibyte String
MB_ONIGURUMA_VERSION
Sockets
Added the following FreeBSD-specific socket options:
SO_LABEL
SO_PEERLABEL
SO_LISTENQLIMIT
SO_LISTENQLEN
SO_USER_COOKIE
Tidy
TIDY_TAG_ARTICLE
TIDY_TAG_ASIDE
TIDY_TAG_AUDIO
TIDY_TAG_BDI
TIDY_TAG_CANVAS
TIDY_TAG_COMMAND
TIDY_TAG_DATALIST
TIDY_TAG_DETAILS
TIDY_TAG_DIALOG
TIDY_TAG_FIGCAPTION
TIDY_TAG_FIGURE
TIDY_TAG_FOOTER
TIDY_TAG_HEADER
TIDY_TAG_HGROUP
TIDY_TAG_MAIN
TIDY_TAG_MARK
TIDY_TAG_MENUITEM
TIDY_TAG_METER
TIDY_TAG_NAV
TIDY_TAG_OUTPUT
TIDY_TAG_PROGRESS
TIDY_TAG_SECTION
TIDY_TAG_SOURCE
TIDY_TAG_SUMMARY
TIDY_TAG_TEMPLATE
TIDY_TAG_TIME
TIDY_TAG_TRACK
TIDY_TAG_VIDEO
Backward Incompatible Changes
PHP Core
Array-style access of non-arrays
Trying to use values of type null, bool,
    int, float or resource as an
    array (such as $null["key"]) will now generate a notice.
get_declared_classes function
The get_declared_classes function no longer
    returns anonymous classes that have not been instantiated yet.
fn keyword
fn is now a reserved keyword. In particular,
    it can no longer be used as a function or class name.
    It can still be used as a method or class constant name.
<?php tag at end of file
<?php at the end of the file (without trailing newline)
    will now be interpreted as an opening PHP tag. Previously it was interpreted
    either as a short opening tag followed by literal php and
    resulted in a syntax error (with short_open_tag=1)
    or was interpreted as a literal <?php string
    (with short_open_tag=0).
Stream wrappers
When using include/require on a stream,
    streamWrapper::stream_set_option
    will be invoked with the STREAM_OPTION_READ_BUFFER option.
    Custom stream wrapper implementations may need to implement the
    streamWrapper::stream_set_option method to
    avoid a warning (always returning  is a sufficient implementation).
Serialization
The o serialization format has been removed.
    As it is never produced by PHP, this may only break unserialization of
    manually crafted strings.
Password algorithm constants
Password hashing algorithm identifiers are now nullable strings rather
    than integers.
PASSWORD_DEFAULT was int 1; now is string '2y' (in PHP 7.4.0, 7.4.1, and 7.4.2 it was )
PASSWORD_BCRYPT was int 1; now is string '2y'
PASSWORD_ARGON2I was int 2; now is string 'argon2i'
PASSWORD_ARGON2ID was int 3; now is string 'argon2id'
Applications correctly using the constants PASSWORD_DEFAULT,
    PASSWORD_BCRYPT, PASSWORD_ARGON2I, and PASSWORD_ARGON2ID will continue to
    function correctly.
htmlentities function
htmlentities will now raise a notice
    (instead of a strict standards warning) if it is used with
    an encoding for which only basic entity substitution is supported,
    in which case it is equivalent to htmlspecialchars.
fread and fwrite function
fread and fwrite will now
    return  if the operation failed.
    Previously an empty string or 0 was returned.
    EAGAIN/EWOULDBLOCK are not considered failures.
These functions now also raise a notice on failure,
    such as when trying to write to a read-only file resource.
BCMath Arbitrary Precision Mathematics
BCMath functions will now warn if a non well-formed number is passed, such
   as "32foo". The argument will be interpreted as zero, as before.
CURL
Attempting to serialize a CURLFile class will now
   generate an exception. Previously the exception was only thrown on unserialization.
Using CURLPIPE_HTTP1 is deprecated, and is no longer
   supported as of cURL 7.62.0.
The $version parameter of curl_version
   is deprecated. If any value not equal to the default CURLVERSION_NOW
   is passed, a warning is raised and the parameter is ignored.
Date and Time
Calling var_dump or similar on a
   DateTime or DateTimeImmutable
   instance will no longer leave behind accessible properties on the object.
Comparison of DateInterval objects
   (using ==, , and so on) will now generate
   a warning and always return . Previously all DateInterval
   objects were considered equal, unless they had properties.
Intl
The default parameter value of idn_to_ascii and
   idn_to_utf8 is now INTL_IDNA_VARIANT_UTS46
   instead of the deprecated INTL_IDNA_VARIANT_2003.
MySQLi
The embedded server functionality has been removed. It was broken since
   at least PHP 7.0.
The undocumented mysqli::$stat property has been removed
   in favor of mysqli::stat.
OpenSSL
The openssl_random_pseudo_bytes function will now
   throw an exception in error situations, similar to random_bytes.
   In particular, an Error is thrown if the number of
   requested bytes is less than or equal to zero, and an Exception
   is thrown if sufficient randomness cannot be gathered.
   The $crypto_strong output argument is guaranteed to always
   be  if the function does not throw, so explicitly checking it is not necessary.
Regular Expressions (Perl-Compatible)
When PREG_UNMATCHED_AS_NULL mode is used, trailing
   unmatched capturing groups will now also be set to  (or
   [null, -1] if offset capture is enabled).
   This means that the size of the $matches will always be the same.
PHP Data Objects
Attempting to serialize a PDO or
   PDOStatement instance will now generate
   an Exception rather than a PDOException,
   consistent with other internal classes which do not support serialization.
Reflection
Reflection objects will now generate an exception if an attempt is made
   to serialize them. Serialization for reflection objects was never
   supported and resulted in corrupted reflection objects. It has been
   explicitly prohibited now.
The values of the class constant of ReflectionClassConstant,
   ReflectionMethod and ReflectionProperty
   have changed.
Standard PHP Library (SPL)
Calling get_object_vars on an ArrayObject
   instance will now always return the properties of the ArrayObject
   itself (or a subclass). Previously it returned the values of the wrapped
   array/object unless the ArrayObject::STD_PROP_LIST
   flag was specified.
Other affected operations are:
ReflectionObject::getProperties
reset, current, etc.
     Use Iterator methods instead.
Potentially others working on object properties as a list,
     e.g. array_walk.
(array) casts are not affected. They will continue to
   return either the wrapped array, or the ArrayObject
   properties, depending on whether the ArrayObject::STD_PROP_LIST
   flag is used.
SplPriorityQueue::setExtractFlags will throw
   an exception if zero is passed. Previously this would generate a recoverable
   fatal error on the next extraction operation.
ArrayObject, ArrayIterator,
   SplDoublyLinkedList and SplObjectStorage
   now support the __serialize() and __unserialize()
   mechanism in addition to the Serializable interface.
   This means that serialization payloads created on older PHP versions can still be
   unserialized, but new payloads created by PHP 7.4 will not be understood by older versions.
Tokenizer
token_get_all will now emit a
   T_BAD_CHARACTER token for unexpected
   characters instead of leaving behind holes in the token stream.
Incoming Cookies
As of PHP 7.4.11, the names of incoming cookies are no
   longer url-decoded for security reasons.
Other Changes
Performance Improvements
PHP Core
A specialized VM opcode for the array_key_exists
    function has been added, which improves performance of this function
    if it can be statically resolved. In namespaced code, this may require
    writing \array_key_exists() or explicitly importing
    the function.
Regular Expressions (Perl-Compatible)
When preg_match in UTF-8 mode ("u" modifier)
    is repeatedly called on the same string (but possibly different offsets),
    it will only be checked for UTF-8 validity once.
Changes to INI File Handling
zend.exception_ignore_args is a new INI directive
   for including or excluding arguments from stack traces generated
   from exceptions.
opcache.preload_user is a new INI directive
   for specifying the user account under which preloading
   code is execute if it would otherwise be run as root (which is not
   allowed for security reasons).
Migration to pkg-config
A number of extensions have been migrated to exclusively use pkg-config for the
   detection of library dependencies. Generally, this means that instead of using
   --with-foo-dir=DIR or similar only
   --with-foo is used. Custom library paths can be
   specified either by adding additional directories to PKG_CONFIG_PATH
   or by explicitly specifying compilation options through FOO_CFLAGS
   and FOO_LIBS.
The following extensions and SAPIs are affected:
CURL:
--with-curl no longer accepts a directory.
Enchant:
--with-enchant no longer accepts a directory.
FPM:
--with-fpm-systemd now uses only pkg-config
       for libsystem checks. The libsystemd minimum required version is 209.
GD:
--with-gd becomes
       --enable-gd
       (whether to enable the extension at all) and
       --with-external-gd
       (to opt into using an external libgd, rather than the bundled one).
--with-png-dir has been removed. libpng is required.
--with-zlib-dir has been removed. zlib is required.
--with-freetype-dir
       becomes --with-freetype
--with-jpeg-dir becomes
       --with-jpeg
--with-webp-dir becomes
       --with-webp
--with-xpm-dir becomes
       --with-xpm
IMAP:
--with-kerberos-systemd no longer accepts a directory.
Intl:
--with-icu-dir has been removed.
       If --enable-intl is passed,
       then libicu is always required.
LDAP:
--with-ldap-sasl no longer accepts a directory.
Libxml:
--with-libxml-dir has been removed.
--enable-libxml becomes
       --with-libxml.
--with-libexpat-dir has been renamed to
       --with-expat and no longer accepts a directory.
Litespeed:
--with-litespeed becomes
       --enable-litespeed.
Mbstring:
--with-onig has been removed.
       Unless --disable-mbregex
       has been passed, libonig is required.
ODBC:
--with-iodbc no longer accepts a directory.
--with-unixODBC without a directory now uses
       pkg-config (preferred). Directory is still accepted for old versions without libodbc.pc.
OpenSSL:
--with-openssl no longer accepts a directory.
PCRE:
--with-pcre-regex has been removed.
       Instead --with-external-pcre
       is provided to opt into using an external PCRE library, rather
       than the bundled one.
PDO_SQLite:
--with-pdo-sqlite no longer accepts a directory.
Readline:
--with-libedit no longer accepts a directory.
Sodium:
--with-sodium no longer accepts a directory.
SQLite3:
--with-sqlite3 no longer accepts a directory.
XSL:
--with-xsl no longer accepts a directory.
Zip:
--with-libzip has been removed.
--enable-zip becomes
       --with-zip.
CSV escaping
fputcsv,
   fgetcsv,
   SplFileObject::fputcsv, 
   SplFileObject::fgetcsv, and
   SplFileObject::setCsvControl
   now accept an empty string as $escape argument,
   which disables the proprietary PHP escaping mechanism.
The behavior of str_getcsv has been
   adjusted accordingly (formerly, an empty string was identical
   to using the default).
SplFileObject::getCsvControl now may also
   return an empty string for the third array element, accordingly.
Data Filtering
The filter extension no longer exposes
   --with-pcre-dir for Unix builds and can now reliably
   be built as shared when using ./configure
GD
The behavior of imagecropauto in the bundled
   libgd has been synced with that of system libgd:
IMG_CROP_DEFAULT is no longer falling
     back to IMG_CROP_SIDES
Threshold-cropping now uses the algorithm of system libgd
The default $mode parameter of
   imagecropauto has been changed to
   IMG_CROP_DEFAULT; passing -1
   is now deprecated.
imagescale now supports aspect ratio preserving
   scaling to a fixed height by passing -1
   as $new_width.
HASH Message Digest Framework
The hash extension cannot be disabled
   anymore and is always an integral part of any PHP build, similar to
   the date extension.
Intl
The intl extension
   now requires at least ICU 50.1.
ResourceBundle now implements
   Countable.
Lightweight Directory Access Protocol
Support for nsldap and umich_ldap has been removed.
Libxml
All libxml-based extensions now require libxml 2.7.6 or newer.
Multibyte String
The oniguruma library is no longer bundled with PHP, instead libonig needs
   to be available on the system. Alternatively
   --disable-mbregex can be used to disable
   the mbregex component.
OPcache
The --disable-opcache-file and
   --enable-opcache-file configure options
   have been removed in favor of the
   opcache.file_cache INI directive.
Password Hashing
The password_hash and
   password_needs_rehash functions
   now accept nullable  and  for $algo argument.
PEAR
Installation of PEAR (including PECL) is no longer enabled by default. It
   can be explicitly enabled using --with-pear.
   This option is deprecated and may be removed in the future.
Reflection
The numeric values of the modifier constants
   (IS_ABSTRACT,
   IS_DEPRECATED,
   IS_EXPLICIT_ABSTRACT,
   IS_FINAL,
   IS_IMPLICIT_ABSTRACT,
   IS_PRIVATE,
   IS_PROTECTED,
   IS_PUBLIC, and
   IS_STATIC) on the
   ReflectionClass,
   ReflectionFunction,
   ReflectionMethod,
   ReflectionObject, and
   ReflectionProperty
   classes have changed.
SimpleXML
SimpleXMLElement now implements
   Countable.
SQLite3
The bundled libsqlite has been removed. To build the
   SQLite3 extension a
   system libsqlite3 ≥ 3.7.4 is now required. To build the
   PDO_SQLite extension
   a system libsqlite3 ≥ 3.5.0 is now required.
Serialization and unserialization of SQLite3,
   SQLite3Stmt and SQLite3Result
   is now explicitly forbidden. Formerly, serialization of instances of
   these classes was possible, but unserialization yielded unusable objects.
The @param notation can now also be used to
   denote SQL query parameters.
Zip
The bundled libzip library has been removed.
   A system libzip >= 0.11 is now necessary to build the
   zip extension.
New Features
PHP Core
Typed properties
Class properties now support type declarations.
    
     

<?php
class User {
    public int $id;
    public string $name;
}
?>

     
    
    The above example will enforce that $user->id can only be
    assigned int values and $user->name can
    only be assigned string values.
Arrow functions
Arrow functions provide a
    shorthand syntax for defining functions
    with implicit by-value scope binding.

    
     

<?php
$factor = 10;
$nums = array_map(fn($n) => $n * $factor, [1, 2, 3, 4]);
// $nums = array(10, 20, 30, 40);
?>
Limited return type covariance and argument type contravariance
The following code will now work:
    
     

<?php
class A {}
class B extends A {}

class Producer {
    public function method(): A {}
}
class ChildProducer extends Producer {
    public function method(): B {}
}
?>

     
    
    Full variance support is only available if autoloading is used. Inside a
    single file only non-cyclic type references are possible, because all
    classes need to be available before they are referenced.
    
     

<?php

/**
 * These classes satisfy the LSP requirements, because C is a subtype of A.
 * However, at the time class B is declared, class C is not yet available
 */
class A
{
    public function method(): A {}
}

class B extends A
{
    // Fatal error: Could not check compatibility between B::method():C and
    // A::method(): A, because class С is not available
    public function method(): С {}
}

class C extends B {}

?>
Null coalescing assignment operator
<?php
$array['key'] ??= computeDefault();
// is roughly equivalent to
if (!isset($array['key'])) {
    $array['key'] = computeDefault();
}
?>
Unpacking inside arrays
<?php
$parts = ['apple', 'pear'];
$fruits = ['banana', 'orange', ...$parts, 'watermelon'];
// ['banana', 'orange', 'apple', 'pear', 'watermelon'];
?>
Numeric literal separator
Numeric literals can contain underscores between digits.
    
     

<?php
6.674_083e-11; // float
299_792_458;   // decimal
0xCAFE_F00D;   // hexadecimal
0b0101_1111;   // binary
?>
Weak references
Weak references allow the programmer to retain a reference to an object
    that does not prevent the object from being destroyed.
Allow exceptions from __toString()
Throwing exceptions from __toString()
    is now permitted. Previously this resulted in a fatal error. Existing
    recoverable fatal errors in string conversions have been converted to
    Error exceptions.
CURL
CURLFile now supports stream wrappers in addition
   to plain file names, if the extension has been built against libcurl >= 7.56.0.
Filter
The FILTER_VALIDATE_FLOAT filter now supports the
   min_range and max_range
   options, with the same semantics as FILTER_VALIDATE_INT.
FFI
FFI is a new extension, which provides a simple way to call
   native functions, access native variables, and create/access
   data structures defined in C libraries.
GD
Added the IMG_FILTER_SCATTER image filter
   to apply a scatter filter to images.
Hash
Added crc32c hash using Castagnoli's polynomial.
   This CRC32 variant is used by storage systems, such as
   iSCSI, SCTP, Btrfs and ext4.
Multibyte String
Added the mb_str_split function, which provides
   the same functionality as str_split, but operating
   on code points rather than bytes.
OPcache
Support for preloading code has been added.
Regular Expressions (Perl-Compatible)
The preg_replace_callback and preg_replace_callback_array
   functions now accept an additional flags argument, with support for the
   PREG_OFFSET_CAPTURE and PREG_UNMATCHED_AS_NULL flags.
   This influences the format of the matches array passed to the callback function.
PDO
The username and password can now be specified as part of the PDO DSN for
   the mysql, mssql, sybase, dblib, firebird and oci drivers. Previously this
   was only supported by the pgsql driver. If a username/password is specified
   both in the constructor and the DSN, the constructor takes precedence.
It is now possible to escape question marks in SQL queries to avoid them
   being interpreted as parameter placeholders. Writing ??
   allows sending a single question mark to the database and e.g. use the
   PostgreSQL JSON key exists (?) operator.
PDO_OCI
PDOStatement::getColumnMeta is now available.
PDO_SQLite
PDOStatement::getAttribute(PDO::SQLITE_ATTR_READONLY_STATEMENT)
   allows checking whether the statement is read-only, i.e. if it doesn't modify
   the database.
PDO::setAttribute(PDO::SQLITE_ATTR_EXTENDED_RESULT_CODES, true)
   enables the use of SQLite3 extended result codes in PDO::errorInfo
   and PDOStatement::errorInfo.
SQLite3
Added SQLite3::lastExtendedErrorCode
   to fetch the last extended result code.
Added SQLite3::enableExtendedResultCodes($enable = true),
   which will make SQLite3::lastErrorCode
   return extended result codes.
Standard
strip_tags() with array of tag names
strip_tags now also accepts an array of allowed tags:
    instead of strip_tags($str, '<a><p>')
    you can now write strip_tags($str, ['a', 'p']).
Custom object serialization
A new mechanism for custom object serialization has been added, which
    uses two new magic methods: __serialize
    and __unserialize.
    
     

<?php
// Returns array containing all the necessary state of the object.
public function __serialize(): array
{
}

// Restores the object state from the given data array.
public function __unserialize(array $data): void
{
}
?>

     
    
    The new serialization mechanism supersedes the
    Serializable interface,
    which will be deprecated in the future.
Array merge functions without arguments
array_merge and array_merge_recursive
    may now be called without any arguments, in which case they will return an empty array.
    This is useful in conjunction with the spread operator, e.g. array_merge(...$arrays).
proc_open function
proc_open now accepts an array instead of a
    string for the command. In this case the process will be opened
    directly (without going through a shell) and PHP will take care of
    any necessary argument escaping.
    
     

<?php
proc_open(['php', '-r', 'echo "Hello World\n";'], $descriptors, $pipes);
?>
proc_open now supports
    redirect and null descriptors.
    
     

<?php
// Like 2>&1 on the shell
proc_open($cmd, [1 => ['pipe', 'w'], 2 => ['redirect', 1]], $pipes);
// Like 2>/dev/null or 2>nul on the shell
proc_open($cmd, [1 => ['pipe', 'w'], 2 => ['null']], $pipes);
?>
argon2i(d) without libargon
password_hash now has the argon2i and argon2id implementations
    from the sodium extension when PHP is built without libargon.
Deprecated Features
PHP Core
Nested ternary operators without explicit parentheses
Nested ternary operations must explicitly use parentheses
    to dictate the order of the operations.  Previously, when used
    without parentheses, the left-associativity would not result
    in the expected behaviour in most cases.
    
     

<?php
1 ? 2 : 3 ? 4 : 5;   // deprecated
(1 ? 2 : 3) ? 4 : 5; // ok
1 ? 2 : (3 ? 4 : 5); // ok
?>
Parentheses are not required when nesting into the middle operand,
    as this is always unambiguous and not affected by associativity:
    
     

1 ? 2 ? 3 : 4 : 5 // ok
Array and string offset access using curly braces
The array and string offset access syntax using curly braces is
    deprecated. Use $var[$idx] instead of
    $var{$idx}.
(real) cast and is_real function
The (real) cast is deprecated,
    use (float) instead.
The is_real function is also deprecated,
    use is_float instead.
Unbinding $this when $this is used
Unbinding $this of a non-static closure
    that uses $this is deprecated.
parent keyword without parent class
Using parent inside a class without a parent
    is deprecated, and will throw a compile-time error in the future.
    Currently an error will only be generated if/when the parent is
    accessed at run-time.
allow_url_include INI option
The allow_url_include
    ini directive is deprecated. Enabling it will generate
    a deprecation notice at startup.
Invalid characters in base conversion functions
Passing invalid characters to base_convert,
    bindec, octdec and
    hexdec will now generate a deprecation notice.
    The result will still be computed as if the invalid characters did not exist.
    Leading and trailing whitespace, as well as prefixes of type 0x (depending on base)
    continue to be allowed.
Using array_key_exists on objects
Using array_key_exists on objects is deprecated.
    Instead either isset or property_exists
    should be used.
Magic quotes functions
The get_magic_quotes_gpc and get_magic_quotes_runtime
    functions are deprecated. They always return .
hebrevc function
The hebrevc function is deprecated.
    It can be replaced with nl2br(hebrev($str)) or,
    preferably, the use of Unicode RTL support.
convert_cyr_string function
The convert_cyr_string function is deprecated.
    It can be replaced by one of mb_convert_string,
    iconv or UConverter.
money_format function
The money_format function is deprecated.
    It can be replaced by the intl NumberFormatter functionality.
ezmlm_hash function
The ezmlm_hash function is deprecated.
restore_include_path function
The restore_include_path function is deprecated.
    It can be replaced by ini_restore('include_path').
Implode with historical parameter order
Passing parameters to implode in reverse order
    is deprecated, use implode($glue, $parts)
    instead of implode($parts, $glue).
COM
Importing type libraries with case-insensitive constant
   registering has been deprecated.
Filter
FILTER_SANITIZE_MAGIC_QUOTES is deprecated,
   use FILTER_SANITIZE_ADD_SLASHES instead.
Multibyte String
Passing a non-string pattern to mb_ereg_replace
   is deprecated. Currently, non-string patterns are interpreted as
   ASCII codepoints. In PHP 8, the pattern will be interpreted as a
   string instead.
Passing the encoding as 3rd parameter to mb_strrpos
   is deprecated. Instead pass a 0 offset, and encoding as 4th parameter.
Lightweight Directory Access Protocol
ldap_control_paged_result_response and
   ldap_control_paged_result are deprecated.
   Pagination controls can be sent along with
   ldap_search instead.
Reflection
Calls to ReflectionType::__toString now generate
   a deprecation notice. This method has been deprecated in favor of
   ReflectionNamedType::getName in the documentation
   since PHP 7.1, but did not throw a deprecation notice for technical reasons.
The export() methods on all Reflection
   classes are deprecated. Construct a Reflection object and
   convert it to string instead:
   
     

<?php
// ReflectionClass::export(Foo::class, false) is:
echo new ReflectionClass(Foo::class), "\n";

// $str = ReflectionClass::export(Foo::class, true) is:
$str = (string) new ReflectionClass(Foo::class);
?>
Socket
The AI_IDN_ALLOW_UNASSIGNED and
   AI_IDN_USE_STD3_ASCII_RULES flags for
   socket_addrinfo_lookup are deprecated,
   due to an upstream deprecation in glibc.
New Classes and Interfaces
cURL
CurlHandle
CurlMultiHandle
CurlShareHandle
Enchant
EnchantBroker
EnchantDictionary
GD
GdImage
OpenSSL
OpenSSLAsymmetricKey
OpenSSLCertificate
OpenSSLCertificateSigningRequest
Shmop
Shmop
Sockets
AddressInfo
Socket
Systen V
SysvMessageQueue
SysvSemaphore
SysvSharedMemory
XML Parser
XMLParser
XMLWriter
XMLWriter
Zlib
DeflateContext
InflateContext
Backward Incompatible Changes
PHP Core
String to Number Comparison
Non-strict comparisons between numbers and non-numeric strings now work by casting the number to
    string and comparing the strings. Comparisons between numbers and numeric strings continue to
    work as before. Notably, this means that 0 == "not-a-number" is considered false
    now.
    
     
      
       
        Comparison
        Before
        After
       
      
      
       
        0 == "0"
        
        
       
       
        0 == "0.0"
        
        
       
       
        0 == "foo"
        
        
       
       
        0 == ""
        
        
       
       
        42 == "   42"
        
        
       
       
        42 == "42foo"
Other incompatible Changes
match is now a reserved keyword.
mixed is now a reserved word, so it cannot be used to name a class, interface or trait, and is also prohibited from being used in namespaces.
Assertion failures now throw by default. If the old behavior is desired,
      assert.exception=0 can be set in the INI settings.
Methods with the same name as the class are no longer interpreted as constructors. The
      __construct() method should be used instead.
The ability to call non-static methods statically has been removed. Thus
      is_callable will fail when checking for a non-static method with a classname
      (must check with an object instance).
The (real) and (unset) casts have been removed.
The track_errors ini directive has been removed. This
       means that php_errormsg is no longer available. The
       error_get_last function may be used instead.
The ability to define case-insensitive constants has been removed. The third argument to
      define may no longer be .
The ability to specify an autoloader using an __autoload function has been
      removed. spl_autoload_register should be used instead.
The errcontext argument will no longer be passed to custom error handlers
      set with set_error_handler.
create_function has been removed. Anonymous functions may be used instead.
each has been removed.  or ArrayIterator
      should be used instead.
The ability to unbind this from closures that were created from a method,
      using Closure::fromCallable or
      ReflectionMethod::getClosure, has been removed.
The ability to unbind this from proper closures that contain uses of
      this has also been removed.
The ability to use array_key_exists with objects has been removed.
      isset or property_exists may be used instead.
The behavior of array_key_exists regarding the type of the
      key parameter has been made consistent with isset and
      normal array access. All key types now use the usual coercions and array/object keys throw a
      TypeError.
Any array that has a number n as its first numeric key will use
      n+1 for its next implicit key, even if n is
      negative.
The default error_reporting level is now E_ALL. Previously it excluded
      E_NOTICE and E_DEPRECATED.
display_startup_errors is now enabled by
      default.
Using parent inside a class that has no parent will now result in a fatal
      compile-time error.
The @ operator will no longer silence fatal errors
      (E_ERROR, E_CORE_ERROR,
      E_COMPILE_ERROR, E_USER_ERROR,
      E_RECOVERABLE_ERROR, E_PARSE). Error handlers that
      expect error_reporting to be 0 when @ is used, should be
      adjusted to use a mask check instead:
<?php
// Replace
function my_error_handler($err_no, $err_msg, $filename, $linenum) {
    if (error_reporting() == 0) {
        return false;
    }
    // ...
}

// With
function my_error_handler($err_no, $err_msg, $filename, $linenum) {
    if (!(error_reporting() & $err_no)) {
        return false;
    }
    // ...
}
?>
Additionally, care should be taken that error messages are not displayed in production
      environments, which can result in information leaks. Please ensure that
      display_errors=Off is used in conjunction with error logging.
#[ is no longer interpreted as the start of a comment,
      as this syntax is now used for attributes.
Inheritance errors due to incompatible method signatures (LSP violations) will now always
      generate a fatal error. Previously a warning was generated in some cases.
The precedence of the concatenation operator has changed relative to bitshifts and addition as
      well as subtraction.
<?php
echo "Sum: " . $a + $b;
// was previously interpreted as:
echo ("Sum: " . $a) + $b;
// is now interpreted as:
echo "Sum:" . ($a + $b);
?>
Arguments with a default value that resolves to  at runtime will no longer implicitly mark
      the argument type as nullable. Either an explicit nullable type, or an explicit  default
      value has to be used instead.
<?php
// Replace
function test(int $arg = CONST_RESOLVING_TO_NULL) {}
// With
function test(?int $arg = CONST_RESOLVING_TO_NULL) {}
// Or
function test(int $arg = null) {}
?>
A number of warnings have been converted into Error exceptions:
Attempting to write to a property of a non-object. Previously this
        implicitly created an stdClass object for null, false and empty strings.
       
       
        Attempting to append an element to an array for which the PHP_INT_MAX key
        is already used.
       
       
        Attempting to use an invalid type (array or object) as an array key or
        string offset.
       
       Attempting to write to an array index of a scalar value.
       Attempting to unpack a non-array/Traversable.
       
        Attempting to access unqualified constants which are undefined.
        Previously, unqualified constant accesses resulted in a warning and were interpreted as strings.
       
       
        Passing the wrong number of arguments to a non-variadic built-in
        function will throw an ArgumentCountError.
       
       
        Passing invalid countable types to count will throw
        a TypeError.
A number of notices have been converted into warnings:
Attempting to read an undefined variable.
       Attempting to read an undefined property.
       Attempting to read an undefined array key.
       Attempting to read a property of a non-object.
       Attempting to access an array index of a non-array.
       Attempting to convert an array to string.
       Attempting to use a resource as an array key.
       Attempting to use null, a boolean, or a float as a string offset.
       Attempting to read an out-of-bounds string offset.
       Attempting to assign an empty string to a string offset.
Attempting to assign multiple bytes to a string offset will now emit a warning.
Unexpected characters in source files (such as NUL bytes outside of strings) will now result in a
      ParseError exception instead of a compile warning.
Uncaught exceptions now go through "clean shutdown", which means that destructors will be called
      after an uncaught exception.
The compile time fatal error "Only variables can be passed by reference" has been delayed until
      runtime, and converted into an "Argument cannot be passed by reference"
      Error exception.
Some "Only variables should be passed by reference" notices have been converted to "Argument
      cannot be passed by reference" exception.
The generated name for anonymous classes has changed. It will now include the name of the first
      parent or interface:
<?php
new class extends ParentClass {};
// -> ParentClass@anonymous
new class implements FirstInterface, SecondInterface {};
// -> FirstInterface@anonymous
new class {};
// -> class@anonymous
?>
The name shown above is still followed by a NUL byte and a unique suffix.
Non-absolute trait method references in trait alias adaptations are now required to be
      unambiguous:
<?php
class X {
    use T1, T2 {
        func as otherFunc;
    }
    function func() {}
}
?>
If both T1::func() and T2::func() exist, this code was previously
      silently accepted, and func was assumed to refer to T1::func. Now it will generate a
      fatal error instead, and either T1::func or T2::func needs to be
      written explicitly.
The signature of abstract methods defined in traits is now checked against the implementing class
      method:
<?php
trait MyTrait {
    abstract private function neededByTrait(): string;
}

class MyClass {
    use MyTrait;

    // Error, because of return type mismatch.
    private function neededByTrait(): int { return 42; }
}
?>
Disabled functions are now treated exactly like non-existent functions. Calling a disabled
      function will report it as unknown, and redefining a disabled function is now possible.
data:// stream wrappers are no longer writable, which matches the documented
      behavior.
The arithmetic and bitwise operators +, -,
      *, /, **, %,
      , , ,
      |, ^, ~, ++,
      -- will now consistently throw a TypeError when one of
      the operands is an ,  or non-overloaded . The only exception to this is
      the array + array merge operation, which remains supported.
Float to string casting will now always behave locale-independently.
<?php
setlocale(LC_ALL, "de_DE");
$f = 3.14;
echo $f, "\n";
// Previously: 3,14
// Now:        3.14
?>
See printf, number_format and
      NumberFormatter for ways to customize number formatting.
Support for deprecated curly braces for offset access has been removed.
<?php
// Instead of:
$array{0};
$array{"key"};
// Write:
$array[0];
$array["key"];
?>
Applying the final modifier on a private method will now produce a warning unless that method is
      the constructor.
If an object constructor exits, the object destructor will no longer be
      called. This matches the behavior when the constructor throws.
Namespaced names can no longer contain whitespace: While Foo\Bar will be recognized
      as a namespaced name, Foo \ Bar will not. Conversely, reserved keywords are now
      permitted as namespace segments, which may also change the interpretation of code:
      new\x is now the same as constant('new\x'), not
      new \x().
Nested ternaries now require explicit parentheses.
debug_backtrace and Exception::getTrace will no
      longer provide references to arguments. It will not be possible to change function arguments
      through the backtrace.
Numeric string handling has been altered to be more intuitive and less error-prone. Trailing
      whitespace is now allowed in numeric strings for consistency with how leading whitespace is
      treated. This mostly affects:
The is_numeric function
       String-to-string comparisons
       Type declarations
       Increment and decrement operations
The concept of a "leading-numeric string" has been mostly dropped; the cases where this remains
      exist in order to ease migration. Strings which emitted an E_NOTICE "A non
      well-formed numeric value encountered" will now emit an E_WARNING "A
      non-numeric value encountered" and all strings which emitted an E_WARNING "A
      non-numeric value encountered" will now throw a
      TypeError. This mostly affects:
Arithmetic operations
       Bitwise operations
This E_WARNING to TypeError change also affects the
      E_WARNING "Illegal string offset 'string'" for illegal string offsets. The
      behavior of explicit casts to int/float from strings has not been changed.
Magic Methods will now have their arguments and return types checked if they have them declared.
      The signatures should match the following list:
__call(string $name, array $arguments): mixed
       __callStatic(string $name, array $arguments): mixed
       __clone(): void
       __debugInfo(): ?array
       __get(string $name): mixed
       __invoke(mixed $arguments): mixed
       __isset(string $name): bool
       __serialize(): array
       __set(string $name, mixed $value): void
       __set_state(array $properties): object
       __sleep(): array
       __unserialize(array $data): void
       __unset(string $name): void
       __wakeup(): void
call_user_func_array array keys will now be interpreted as parameter names,
      instead of being silently ignored.
Declaring a function called assert() inside a namespace is
      no longer allowed, and issues E_COMPILE_ERROR.
      The assert function is subject to special handling by the engine,
      which may lead to inconsistent behavior when defining a namespaced function with the same name.
Resource to Object Migration
Several s have been migrated to s.
   Return value checks using is_resource should be replaced with checks for .
curl_init will now return a CurlHandle object rather
      than a . The curl_close function no longer has an effect,
      instead the CurlHandle instance is automatically destroyed if it is no
      longer referenced.
curl_multi_init will now return a CurlMultiHandle
      object rather than a . The curl_multi_close function no
      longer has an effect, instead the CurlMultiHandle instance is
      automatically destroyed if it is no longer referenced.
curl_share_init will now return a CurlShareHandle
      object rather than a . The curl_share_close function no
      longer has an effect, instead the CurlShareHandle instance is
      automatically destroyed if it is no longer referenced.
enchant_broker_init will now return an EnchantBroker
     object rather than a .
enchant_broker_request_dict and
     enchant_broker_request_pwl_dict will now return an
     EnchantDictionary object rather than a .
The GD extension now uses GdImage objects as the underlying data structure
     for images, rather than s.
     The imagedestroy function no longer has an effect; instead the
     GdImage instance is automatically destroyed if it is no longer referenced.
openssl_x509_read and openssl_csr_sign will now return
     an OpenSSLCertificate object rather than a .
     The openssl_x509_free function is deprecated and no longer has an effect,
     instead the OpenSSLCertificate instance is automatically destroyed if it
     is no longer referenced.
openssl_csr_new will now return an
     OpenSSLCertificateSigningRequest object rather than a .
openssl_pkey_new will now return an
     OpenSSLAsymmetricKey object rather than a .
     The openssl_pkey_free function is deprecated and no longer has an effect,
     instead the OpenSSLAsymmetricKey instance is automatically destroyed if it
     is no longer referenced.
shmop_open will now return a Shmop object rather than
     a . The shmop_close function no longer has an effect, and is
     deprecated; instead the Shmop instance is automatically destroyed if it is
     no longer referenced.
socket_create, socket_create_listen,
     socket_accept, socket_import_stream,
     socket_addrinfo_connect, socket_addrinfo_bind, and
     socket_wsaprotocol_info_import will now return a
     Socket object rather than a .
     socket_addrinfo_lookup will now return an array of
     AddressInfo objects rather than s.
msg_get_queue will now return an SysvMessageQueue
     object rather than a .
sem_get will now return an SysvSemaphore object
     rather than a .
shm_attach will now return an SysvSharedMemory object
     rather than a .
xml_parser_create and xml_parser_create_ns will now
     return an XMLParser object rather than a . The
     xml_parser_free function no longer has an effect, instead the XMLParser
     instance is automatically destroyed if it is no longer referenced.
The XMLWriter functions now accept and return, respectively,
     XMLWriter objects instead of s.
inflate_init will now return an InflateContext object
     rather than a .
deflate_init will now return a DeflateContext object
     rather than a .
COM and .Net (Windows)
The ability to import case-insensitive constants from type libraries has been removed.
   The second argument to com_load_typelib may no longer be false;
   com.autoregister_casesensitive
   may no longer be disabled; case-insensitive markers in
   com.typelib_file are ignored.
CURL
CURLOPT_POSTFIELDS no longer accepts objects as arrays. To
   interpret an object as an array, perform an explicit (array) cast. The
   same applies to other options accepting arrays as well.
Date and Time
mktime and gmmktime now require at least one
   argument. time can be used to get the current timestamp.
DOM
Unimplemented classes from the DOM extension that had no behavior and contained test
   data have been removed. These classes have also been removed in the latest version of
   the DOM standard:
DOMNameList
    DomImplementationList
    DOMConfiguration
    DomError
    DomErrorHandler
    DOMImplementationSource
    DOMLocator
    DOMUserDataHandler
    DOMTypeInfo
    DOMStringExtend
Unimplemented methods from the DOM extension that had no behavior have been removed:
DOMNamedNodeMap::setNamedItem
    DOMNamedNodeMap::removeNamedItem
    DOMNamedNodeMap::setNamedItemNS
    DOMNamedNodeMap::removeNamedItemNS
    DOMText::replaceWholeText
    DOMNode::compareDocumentPosition
    DOMNode::isEqualNode
    DOMNode::getFeature
    DOMNode::setUserData
    DOMNode::getUserData
    DOMDocument::renameNode
Enchant
enchant_broker_list_dicts, enchant_broker_describe and
     enchant_dict_suggest will now return an empty array instead of .
Exif
read_exif_data has been removed; exif_read_data
   should be used instead.
Filter
The FILTER_FLAG_SCHEME_REQUIRED and
     FILTER_FLAG_HOST_REQUIRED flags for the
     FILTER_VALIDATE_URL filter have been removed. The scheme
     and host are (and have been) always required.
The INPUT_REQUEST and INPUT_SESSION source for
     filter_input etc. have been removed. These were never implemented and their
     use always generated a warning.
GD
The deprecated function image2wbmp has been removed.
The deprecated functions png2wbmp and jpeg2wbmp have
     been removed.
The default mode parameter of imagecropauto no longer
     accepts -1. IMG_CROP_DEFAULT should be used instead.
On Windows, php_gd2.dll has been renamed to php_gd.dll.
GMP
gmp_random has been removed. One of gmp_random_range or
   gmp_random_bits should be used instead.
Iconv
iconv implementations which do not properly set errno in case of errors are no
   longer supported.
IMAP
The unused default_host argument of imap_headerinfo
     has been removed.
The imap_header function which is an alias of
     imap_headerinfo has been removed.
Internationalization Functions
The deprecated constant INTL_IDNA_VARIANT_2003 has been removed.
The deprecated Normalizer::NONE constant has been removed.
LDAP
The deprecated functions ldap_sort,
     ldap_control_paged_result and
     ldap_control_paged_result_response have been removed.
The interface of ldap_set_rebind_proc has changed; the
     callback parameter does not accept empty strings anymore;  should be
     used instead.
MBString
The mbstring.func_overload directive has been
     removed. The related MB_OVERLOAD_MAIL,
     MB_OVERLOAD_STRING, and MB_OVERLOAD_REGEX constants
     have also been removed. Finally, the "func_overload" and
     "func_overload_list" entries in mb_get_info have been
     removed.
mb_parse_str can no longer be used without specifying a result array.
A number of deprecated mbregex aliases have been removed. See the following
     list for which functions should be used instead:
mbregex_encoding → mb_regex_encoding
      mbereg → mb_ereg
      mberegi → mb_eregi
      mbereg_replace → mb_ereg_replace
      mberegi_replace → mb_eregi_replace
      mbsplit → mb_split
      mbereg_match → mb_ereg_match
      mbereg_search → mb_ereg_search
      mbereg_search_pos → mb_ereg_search_pos
      mbereg_search_regs → mb_ereg_search_regs
      mbereg_search_init → mb_ereg_search_init
      mbereg_search_getregs → mb_ereg_search_getregs
      mbereg_search_getpos → mb_ereg_search_getpos
      mbereg_search_setpos → mb_ereg_search_setpos
The e modifier for mb_ereg_replace has been removed.
     mb_ereg_replace_callback should be used instead.
A non-string pattern argument to mb_ereg_replace will now be interpreted as
     a string instead of an ASCII codepoint. The previous behavior may be restored with an explicit
     call to chr.
The needle argument for mb_strpos,
     mb_strrpos, mb_stripos,
     mb_strripos, mb_strstr,
     mb_stristr, mb_strrchr and
     mb_strrichr can now be empty.
The is_hex parameter, which was not used internally, has been removed from
     mb_decode_numericentity.
The legacy behavior of passing the encoding as the third argument instead of an offset for the
     mb_strrpos function has been removed; an explicit 0
     offset with the encoding should be provided as the fourth argument instead.
The ISO_8859-* character encoding aliases have been replaced by
     ISO8859-* aliases for better interoperability with the iconv extension. The
     mbregex ISO 8859 aliases with underscores (ISO_8859_* and
     ISO8859_*) have also been removed.
mb_ereg and mb_eregi will now return boolean  on
     a successful match. Previously they returned integer 1 if
     matches was not passed, or max(1, strlen($matches[0])) if
     matches was passed.
OCI8
The OCI-Lob class is now called OCILob, and the
     OCI-Collection class is now called OCICollection
     for name compliance enforced by PHP 8 arginfo type annotation tooling.
Several alias functions have been marked as deprecated.
oci_internal_debug and its alias ociinternaldebug have
     been removed.
ODBC
odbc_connect no longer reuses connections.
The unused flags parameter of odbc_exec has been
     removed.
OpenSSL
openssl_seal and openssl_open now require
     method to be passed, as the previous default of "RC4"
     is considered insecure.
Regular Expressions (Perl-Compatible)
When passing invalid escape sequences they are no longer interpreted as literals. This behavior
   previously required the X modifier – which is now ignored.
PHP Data Objects
The default error handling mode has been changed from "silent" to "exceptions". See
     Errors and error handling for details.
The signatures of some PDO methods have changed:
PDO::query(string $query, ?int $fetchMode  = null, mixed  ...$fetchModeArgs)
      PDOStatement::setFetchMode(int $mode, mixed ...$args)
PDO ODBC
The  directive
   pdo_odbc.db2_instance_name has been
   removed.
PDO MySQL
PDO::inTransaction now reports the actual transaction state of
   the connection, rather than an approximation maintained by PDO. If a query that is
   subject to "implicit commit" is executed, PDO::inTransaction
   will subsequently return , as a transaction is no longer active.
PostgreSQL
The deprecated pg_connect syntax using multiple parameters instead of a
     connection string is no longer supported.
The deprecated pg_lo_import and pg_lo_export signature
     that passes the connection as the last argument is no longer supported. The connection should be
     passed as first argument instead.
pg_fetch_all will now return an empty array instead of  for result
     sets with zero rows.
Phar
Metadata associated with a phar will no longer be automatically unserialized, to fix potential
   security vulnerabilities due to object instantiation, autoloading, etc.
Reflection
The method signatures
ReflectionClass::newInstance($args)
      ReflectionFunction::invoke($args)
      ReflectionMethod::invoke($object, $args)
have been changed to:
ReflectionClass::newInstance(...$args)
      ReflectionFunction::invoke(...$args)
      ReflectionMethod::invoke($object, ...$args)
Code that must be compatible with both PHP 7 and PHP 8 can use the following
     signatures to be compatible with both versions:
ReflectionClass::newInstance($arg = null, ...$args)
      ReflectionFunction::invoke($arg = null, ...$args)
      ReflectionMethod::invoke($object, $arg = null, ...$args)
The ReflectionType::__toString method will now return a complete debug
     representation of the type, and is no longer deprecated. In particular the result will include a
     nullability indicator for nullable types. The format of the return value is not stable and may
     change between PHP versions.
Reflection export() methods have been removed.
     Instead reflection objects can be cast to string.
ReflectionMethod::isConstructor and
     ReflectionMethod::isDestructor now also return  for
     __construct() and
     __destruct() methods of interfaces.
     Previously, this would only be true for methods of classes and traits.
ReflectionType::isBuiltin method has been moved to
     ReflectionNamedType. ReflectionUnionType does not
     have it.
Sockets
The deprecated AI_IDN_ALLOW_UNASSIGNED and
     AI_IDN_USE_STD3_ASCII_RULES flags for
     socket_addrinfo_lookup have been removed.
Standard PHP Library (SPL)
SplFileObject::fgetss has been removed.
SplFileObject::seek now always seeks to the beginning of the line.
     Previously, positions =1 sought to the beginning of the next line.
SplHeap::compare now specifies a method signature. Inheriting classes
     implementing this method will now have to use a compatible method signature.
SplDoublyLinkedList::push,
     SplDoublyLinkedList::unshift and
     SplQueue::enqueue now return void instead of .
spl_autoload_register will now always throw a
     TypeError on invalid arguments, therefore the second argument
     do_throw is ignored and a notice will be emitted if it is set to .
SplFixedArray is now an IteratorAggregate
     and not an Iterator.
     SplFixedArray::rewind, SplFixedArray::current,
     SplFixedArray::key, SplFixedArray::next, and
     SplFixedArray::valid have been removed. In their place,
     SplFixedArray::getIterator has been added. Any code which uses explicit
     iteration over SplFixedArray must now obtain an
     Iterator through
     SplFixedArray::getIterator. This means that
     SplFixedArray is now safe to use in nested loops.
Standard Library
assert will no longer evaluate string arguments, instead they will be
     treated like any other argument. assert($a == $b) should be used instead of
     assert('$a == $b'). The assert.quiet_eval ini directive and the
     ASSERT_QUIET_EVAL constant have also been removed, as they would no longer
     have any effect.
parse_str can no longer be used without specifying a result array.
The string.strip_tags filter has been removed.
The needle argument of strpos,
     strrpos, stripos, strripos,
     strstr, strchr, strrchr, and
     stristr will now always be interpreted as a string. Previously non-string
     needles were interpreted as an ASCII code point. An explicit call to chr can
     be used to restore the previous behavior.
The needle argument for strpos,
     strrpos, stripos, strripos,
     strstr, stristr and strrchr can
     now be empty.
The length argument for substr,
     substr_count, substr_compare, and
     iconv_substr can now be .  values will behave as if no length
     argument was provided and will therefore return the remainder of the string instead of an empty
     string.
The length argument for array_splice can now be
     .  values will behave identically to omitting the argument, thus removing everything
     from the offset to the end of the array.
The args argument of vsprintf,
     vfprintf, and vprintf must now be an array. Previously
     any type was accepted.
The 'salt' option of password_hash is no longer
     supported. If the 'salt' option is used a warning is generated, the provided
     salt is ignored, and a generated salt is used instead.
The quotemeta function will now return an empty string if an empty string
     was passed. Previously  was returned.
The following functions have been removed:
hebrevc
      convert_cyr_string
      money_format
      ezmlm_hash
      restore_include_path
      get_magic_quotes_gpc
      get_magic_quotes_runtime
      fgetss
FILTER_SANITIZE_MAGIC_QUOTES has been removed.
Calling implode with parameters in a reverse order ($pieces,
     $glue) is no longer supported.
parse_url will now distinguish absent and empty queries and fragments:
http://example.com/foo → query = null, fragment = null
      http://example.com/foo? → query = "",   fragment = null
      http://example.com/foo# → query = null, fragment = ""
      http://example.com/foo?# → query = "",   fragment = ""
     
      Previously all cases resulted in query and fragment being .
var_dump and debug_zval_dump will now print
     floating-point numbers using serialize_precision
     rather than precision. In a default configuration, this
     means that floating-point numbers are now printed with full accuracy by these debugging
     functions.
If the array returned by __sleep() contains non-existing
     properties, these are now silently ignored. Previously, such properties would have been
     serialized as if they had the value .
The default locale on startup is now always "C". No locales are inherited from
     the environment by default. Previously, LC_ALL was set to
     "C", while LC_CTYPE was inherited from the environment.
     However, some functions did not respect the inherited locale without an explicit
     setlocale call. An explicit setlocale call is now
     always required if a locale component should be changed from the default.
The deprecated DES fallback in crypt has been removed. If an unknown salt
     format is passed to crypt, the function will fail with *0
     instead of falling back to a weak DES hash now.
Specifying out of range rounds for SHA256/SHA512 crypt will now fail with
     *0 instead of clamping to the closest limit. This matches glibc behavior.
The result of sorting functions may have changed, if the array contains elements that compare as
     equal.
Any functions accepting callbacks that are not explicitly specified to accept parameters by
     reference will now warn if a callback with reference parameters is used. Examples include
     array_filter and array_reduce. This was already the
     case for most, but not all, functions previously.
The HTTP stream wrapper as used by functions like file_get_contents
     now advertises HTTP/1.1 rather than HTTP/1.0 by default. This does not change the behavior of the
     client, but may cause servers to respond differently. To retain the old behavior, set the
     'protocol_version' stream context option, e.g.
<?php
$ctx = stream_context_create(['http' => ['protocol_version' => '1.0']]);
echo file_get_contents('http://example.org', false, $ctx);
?>
Calling crypt without an explicit salt is no longer supported. If you would
     like to produce a strong hash with an auto-generated salt, use
     password_hash instead.
substr, mb_substr, iconv_substr and
    grapheme_substr now consistently clamp out-of-bounds offsets to the string
    boundary. Previously,  was returned instead of the empty string in some cases.
On Windows, the program execution functions (proc_open, exec,
     popen etc.) using the shell, now consistently execute %comspec% /s
     /c "$commandline", which has the same effect as executing
     $commandline (without additional quotes).
Sysvsem
The auto_release parameter of sem_get was changed to
     accept bool values rather than int.
Tidy
The use_include_path parameter, which was not used internally, has been
     removed from tidy_repair_string.
tidy::repairString and tidy::repairFile became
     static methods.
Tokenizer
T_COMMENT tokens will no longer include a trailing newline. The newline will
     instead be part of a following T_WHITESPACE token. It should be noted that
     T_COMMENT is not always followed by whitespace, it may also be followed by
     T_CLOSE_TAG or end-of-file.
Namespaced names are now represented using the T_NAME_QUALIFIED
     (Foo\Bar), T_NAME_FULLY_QUALIFIED (\Foo\Bar) and
     T_NAME_RELATIVE (namespace\Foo\Bar) tokens.
     T_NS_SEPARATOR is only used for standalone namespace separators, and only
     syntactially valid in conjunction with group use declarations.
XMLReader
XMLReader::open and XMLReader::XML are now
   static methods. They can still be called as instance methods, but inheriting classes need to declare them
   as static if they override these methods.
XML-RPC
The XML-RPC extension has been moved to PECL and is no longer part of the PHP
   distribution.
Zip
ZipArchive::OPSYS_Z_CPM has been removed (this name was a typo). Use
   ZipArchive::OPSYS_CPM instead.
Zlib
gzgetss has been removed.
zlib.output_compression is no longer
     automatically disabled for Content-Type: image/*.
Windows PHP Test Packs
The test runner has been renamed from run-test.php to
   run-tests.php, to match its name in php-src.
Other Changes
Changes in SAPI Modules
Apache2Handler
The PHP module has been renamed from php7_module to
    php_module.
Changed Functions
Reflection
ReflectionClass::getConstants and
    ReflectionClass::getReflectionConstants results can be now filtered via
    a new parameter filter. Three new constants were added to be used with it:
ReflectionClassConstant::IS_PUBLIC
     ReflectionClassConstant::IS_PROTECTED
     ReflectionClassConstant::IS_PRIVATE
Standard
The math functions abs, ceil,
    floor and round now properly heed
    the strict_types directive.
    Previously, they coerced the first argument even in strict type mode.
Zip
The ZipArchive::addGlob and
      ZipArchive::addPattern methods accept more values in the
      options array argument:
flags
       comp_method
       comp_flags
       env_method
       enc_password
ZipArchive::addEmptyDir, ZipArchive::addFile
      and ZipArchive::addFromString
      methods have a new flags argument. This allows managing name encoding
      (ZipArchive::FL_ENC_*) and entry replacement
      (ZipArchive::FL_OVERWRITE).
ZipArchive::extractTo now restores the file modification time.
Other Changes to Extensions
CURL
The CURL extension now requires at least libcurl 7.29.0.
The deprecated parameter version of curl_version has
      been removed.
Date and Time
DatePeriod now implements IteratorAggregate
    (instead of Traversable).
DOM
DOMNamedNodeMap and DOMNodeList now implement
    IteratorAggregate (instead of
    Traversable).
Intl
IntlBreakIterator and ResourceBundle now implement
    IteratorAggregate (instead of Traversable).
Enchant
The enchant extension now uses libenchant-2 by default when available. libenchant version 1 is
    still supported but is deprecated and could be removed in the future.
GD
The num_points parameter of imagepolygon,
      imageopenpolygon and imagefilledpolygon is now
      optional, i.e. these functions may be called with either 3 or 4 arguments. If the argument is
      omitted, it is calculated as count($points)/2.
The function imagegetinterpolation to get the current interpolation method
      has been added.
JSON
The JSON extension cannot be disabled anymore and is always an integral part of any PHP build,
    similar to the date extension.
MBString
The Unicode data tables have been updated to version 13.0.0.
PDO
PDOStatement now implements
    IteratorAggregate (instead of
    Traversable).
LibXML
The minimum required libxml version is now 2.9.0. This means that external entity loading is now
    guaranteed to be disabled by default, and no extra steps need to be taken to protect against XXE
    attacks.
MySQLi / PDO MySQL
When mysqlnd is not used (which is the default and recommended option), the minimum supported
      libmysqlclient version is now 5.5.
mysqli_result now implements
      IteratorAggregate (instead of
      Traversable).
PGSQL / PDO PGSQL
The PGSQL and PDO PGSQL extensions now require at least libpq 9.1.
Readline
Calling readline_completion_function before the interactive prompt starts
    (e.g. in auto_prepend_file) will now override the
    default interactive prompt completion function. Previously,
    readline_completion_function only worked when called after starting the
    interactive prompt.
SimpleXML
SimpleXMLElement now implements
    RecursiveIterator and absorbed the functionality of
    SimpleXMLIterator. SimpleXMLIterator is an empty
    extension of SimpleXMLElement.
Changes to INI File Handling
com.dotnet_version
     is a new INI directive to choose the version of the .NET framework to use for
     dotnet objects.
zend.exception_string_param_max_len
     is a new INI directive to set the maximum string length in an argument of a stringified
     stack strace.
EBCDIC
EBCDIC targets are no longer supported, though it's unlikely that they were still working in the
   first place.
Performance
A Just-In-Time (JIT) compiler has been added to the opcache extension.
array_slice on an array without gaps will no longer scan the whole array
     to find the start offset. This may significantly reduce the runtime of the function with large
     offsets and small lengths.
strtolower now uses a SIMD implementation when using the
     "C" LC_CTYPE locale (which is the default).
New Features
PHP Core
Named Arguments
Support for Named Arguments has been added.
Attributes
Support for Attributes has been added.
Constructor Property Promotion
Support for constructor property promotion (declaring properties in the constructor signature)
    has been added.
Union Types
Support for union types has been added.
Match Expression
Support for match expressions has been added.
Nullsafe Operator
Support for the nullsafe operator (?->) has been added.
Other new Features
The WeakMap class has been added.
The ValueError class has been added.
Any number of function parameters may now be replaced by a variadic argument, as long as the
      types are compatible. For example, the following code is now allowed:
<?php
class A {
     public function method(int $many, string $parameters, $here) {}
}
class B extends A {
     public function method(...$everything) {}
}
?>
static (as in "late static binding") can now be used as a return type:
<?php
class Test {
     public function create(): static {
          return new static();
     }
}
?>
It is now possible to fetch the class name of an object using
      $object::class. The result is the same as get_class($object).
and  can now be used with arbitrary expressions,
      using new (expression)(...$args) and $obj instanceof (expression).
Some consistency fixes to variable syntax have been applied, for example writing
      Foo::BAR::$baz is now allowed.
Added Stringable interface, which is automatically implemented if
      a class defines a __toString() method.
Traits can now define abstract private methods.
      Such methods must be implemented by the class using the trait.
throw can now be used as an expression.
      That allows usages like:
      

<?php
$fn = fn() => throw new Exception('Exception in arrow function');
$user = $session->user ?? throw new Exception('Must have user');
An optional trailing comma is now allowed in parameter lists.
      

<?php
function functionWithLongSignature(
    Type1 $parameter1,
    Type2 $parameter2, // <-- This comma is now allowed.
) {
}
It is now possible to write catch (Exception) to catch an exception without storing
      it in a variable.
Support for mixed type has been added.
Private methods declared on a parent class no longer enforce any inheritance rules on the methods
      of a child class (with the exception of final private constructors).
      The following example illustrates which restrictions have been removed:
      

<?php
class ParentClass {
    private function method1() {}
    private function method2() {}
    private static function method3() {}
    // Throws a warning, as "final" no longer has an effect:
    private final function method4() {}
}
class ChildClass extends ParentClass {
    // All of the following are now allowed, even though the modifiers aren't
    // the same as for the private methods in the parent class.
    public abstract function method1() {}
    public static function method2() {}
    public function method3() {}
    public function method4() {}
}
?>
get_resource_id has been added, which returns the same value as
      (int) $resource. It provides the same functionality under a clearer API.
The InternalIterator has been added.
Date and Time
DateTime::createFromInterface and
     DateTimeImmutable::createFromInterface have been added.
The DateTime format specifier p has been added, which is the same as
     P but returns Z rather than +00:00
     for UTC.
DOM
DOMParentNode and DOMChildNode with
   new traversal and manipulation APIs have been added.
Filter
FILTER_VALIDATE_BOOL has been added as an alias for
   FILTER_VALIDATE_BOOLEAN. The new name is preferred, as it uses the canonical
   type name.
Enchant
enchant_dict_add, enchant_dict_is_added, and
   LIBENCHANT_VERSION have been added.
FPM
Added a new option pm.status_listen that allows getting the status from
   different endpoint (e.g. port or UDS file) which is useful for getting the status when all
   children are busy with serving long running requests.
Hash
HashContext objects can now be serialized.
Internationalization Functions
The IntlDateFormatter::RELATIVE_FULL,
   IntlDateFormatter::RELATIVE_LONG,
   IntlDateFormatter::RELATIVE_MEDIUM, and
   IntlDateFormatter::RELATIVE_SHORT
   constants have been added.
LDAP
ldap_count_references has been added, which returns the number
   of reference messages in a search result.
OPcache
If the opcache.record_warnings ini setting is
   enabled, OPcache will record compile-time warnings and replay them on the next include, even if
   it is served from cache.
OpenSSL
Added Cryptographic Message Syntax (CMS) (RFC 5652)
   support composed of functions for encryption, decryption, signing, verifying and reading. The API
   is similar to the API for PKCS #7 functions with an addition of new encoding constants:
   OPENSSL_ENCODING_DER, OPENSSL_ENCODING_SMIME
   and OPENSSL_ENCODING_PEM:
   
    
     openssl_cms_encrypt encrypts the message in the file with the certificates
     and outputs the result to the supplied file.
    
    
     openssl_cms_decrypt that decrypts the S/MIME message in the file and outputs
     the results to the supplied file.
    
    
     openssl_cms_read that exports the CMS file to an array
     of PEM certificates.
    
    
     openssl_cms_sign that signs the MIME message in the file with a cert and key
     and output the result to the supplied file.
    
    
     openssl_cms_verify that verifies that the data block is intact, the signer
     is who they say they are, and returns the certs of the signers.
Regular Expressions (Perl-Compatible)
preg_last_error_msg has been added, which returns a human-readable message for the last
   PCRE error. It complements preg_last_error, which returns an integer enum value
   instead.
Reflection
The following methods can now return information about default values of
     parameters of internal functions:
ReflectionParameter::isDefaultValueAvailable
      ReflectionParameter::getDefaultValue
      ReflectionParameter::isDefaultValueConstant
      ReflectionParameter::getDefaultValueConstantName
SQLite3
SQLite3::setAuthorizer and respective class constants have been added
   to set a userland callback that will be used to authorize or not an action on the database.
Standard Library
str_contains, str_starts_with and
     str_ends_with have been added, which check whether haystack contains,
     starts with or ends with needle, respectively.
fdiv has been added, which performs a floating-point division under IEEE 754 semantics.
     Division by zero is considered well-defined and will return one of Inf,
     -Inf or NaN.
get_debug_type has been added, which returns a type useful for error messages. Unlike
     gettype, it uses canonical type names, returns class names for objects, and
     indicates the resource type for resources.
printf and friends now support the %h and
     %H format specifiers. These are the same as %g and
     %G, but always use "." as the decimal separator, rather
     than determining it through the LC_NUMERIC locale.
printf and friends now support using "*" as width or
     precision, in which case the width/precision is passed as an argument to printf. This also allows
     using precision -1 with %g, %G,
     %h and %H. For example, the following code can be used to
     reproduce PHP's default floating point formatting:
<?php
printf("%.*H", (int) ini_get("precision"), $float);
printf("%.*H", (int) ini_get("serialize_precision"), $float);
?>
proc_open now supports pseudo-terminal (PTY) descriptors. The following
     attaches stdin, stdout and stderr to the
     same PTY:
<?php
$proc = proc_open($command, [['pty'], ['pty'], ['pty']], $pipes);
?>
proc_open now supports socket pair descriptors. The following attaches a
     distinct socket pair to stdin, stdout and
     stderr:
<?php
$proc = proc_open($command, [['socket'], ['socket'], ['socket']], $pipes);
?>
Unlike pipes, sockets do not suffer from blocking I/O issues on Windows. However, not all
     programs may work correctly with stdio sockets.
Sorting functions are now stable, which means that equal-comparing elements will retain their
     original order.
array_diff, array_intersect and their variations can
     now be used with a single array as argument. This means that usages like the following are now
     possible:
<?php
// OK even if $excludes is empty:
array_diff($array, ...$excludes);
// OK even if $arrays only contains a single array:
array_intersect(...$arrays);
?>
The flag parameter of ob_implicit_flush was changed
     to accept a bool rather than an int.
Tokenizer
PhpToken adds an object-based interface to the tokenizer. It provides a
   more uniform and ergonomic representation, while being more memory efficient and faster.
Zip
The Zip extension has been updated to version 1.19.1.
New ZipArchive::setMtimeName and
     ZipArchive::setMtimeIndex to set the modification time of an entry.
New ZipArchive::registerProgressCallback to provide updates during archive close.
New ZipArchive::registerCancelCallback to allow cancellation during archive
     close.
New ZipArchive::replaceFile to replace an entry content.
New ZipArchive::isCompressionMethodSupported to check optional compression
     features.
New ZipArchive::isEncryptionMethodSupported to check optional encryption
     features.
The ZipArchive::lastId property to get the index value of
     the last added entry has been added.
Errors can now be checked after an archive has been closed using the
     ZipArchive::status and
     ZipArchive::statusSys properties, or the
     ZipArchive::getStatusString method.
The 'remove_path' option of ZipArchive::addGlob and
     ZipArchive::addPattern is now treated as an arbitrary string prefix (for
     consistency with the 'add_path' option), whereas formerly it was treated as a
     directory name.
Optional compression / encryption features are now listed in phpinfo.
Deprecated Features
PHP Core
If a parameter with a default value is followed by a required parameter, the default value has
     no effect. This is deprecated as of PHP 8.0.0 and can generally be resolved by dropping the
     default value, without a change in functionality:
<?php
function test($a = [], $b) {} // Before
function test($a, $b) {}      // After
?>
One exception to this rule are parameters of the form Type $param = null, where
     the null default makes the type implicitly nullable. This usage remains allowed, but it is
     recommended to use an explicit nullable type instead:
<?php
function test(A $a = null, $b) {} // Still allowed
function test(?A $a, $b) {}       // Recommended
?>
Calling get_defined_functions with exclude_disabled
     explicitly set to  is deprecated and no longer has an effect.
     get_defined_functions will never include disabled functions.
Enchant
enchant_broker_set_dict_path and
     enchant_broker_get_dict_path
     are deprecated, because that functionality is neither available in libenchant  1.5 nor in
     libenchant-2.
enchant_dict_add_to_personal is deprecated; use
     enchant_dict_add instead.
enchant_dict_is_in_session is deprecated; use
     enchant_dict_is_added instead.
enchant_broker_free and enchant_broker_free_dict are
     deprecated; unset the object instead.
The ENCHANT_MYSPELL and ENCHANT_ISPELL constants are
     deprecated.
LibXML
libxml_disable_entity_loader has been deprecated. As libxml 2.9.0 is now
   required, external entity loading is guaranteed to be disabled by default, and this function is
   no longer needed to protect against XXE attacks, unless the (still vulnerable)
   LIBXML_NOENT is used.
   In that case, it is recommended to refactor the code using
   libxml_set_external_entity_loader to suppress loading of external entities.
PGSQL / PDO PGSQL
The constant PGSQL_LIBPQ_VERSION_STR now has the same value as
     PGSQL_LIBPQ_VERSION, and thus is deprecated.
Function aliases in the pgsql extension have been deprecated.
     See the following list for which functions should be used instead:
pg_errormessage → pg_last_error
      pg_numrows → pg_num_rows
      pg_numfields → pg_num_fields
      pg_cmdtuples → pg_affected_rows
      pg_fieldname → pg_field_name
      pg_fieldsize → pg_field_size
      pg_fieldtype → pg_field_type
      pg_fieldnum → pg_field_num
      pg_result → pg_fetch_result
      pg_fieldprtlen → pg_field_prtlen
      pg_fieldisnull → pg_field_is_null
      pg_freeresult → pg_free_result
      pg_getlastoid → pg_last_oid
      pg_locreate → pg_lo_create
      pg_lounlink → pg_lo_unlink
      pg_loopen → pg_lo_open
      pg_loclose → pg_lo_close
      pg_loread → pg_lo_read
      pg_lowrite → pg_lo_write
      pg_loreadall → pg_lo_read_all
      pg_loimport → pg_lo_import
      pg_loexport → pg_lo_export
      pg_setclientencoding → pg_set_client_encoding
      pg_clientencoding -> pg_client_encoding
Standard Library
Sort comparison functions that return  or  will now throw a deprecation warning, and
     should be replaced with an implementation that returns an integer less than, equal to, or greater
     than zero.
<?php
// Replace
usort($array, fn($a, $b) => $a > $b);
// With
usort($array, fn($a, $b) => $a <=> $b);
?>
Zip
Using an empty file as ZipArchive is deprecated. Libzip 1.6.0 does not accept empty files as
     valid zip archives any longer. The existing workaround will be removed in the next version.
The procedural API of Zip is deprecated. Use ZipArchive instead.
     Iteration over all entries can be accomplished using ZipArchive::statIndex
     and a for loop:
<?php
// iterate using the procedural API
assert(is_resource($zip));
while ($entry = zip_read($zip)) {
    echo zip_entry_name($entry);
}

// iterate using the object-oriented API
assert($zip instanceof ZipArchive);
for ($i = 0; $entry = $zip->statIndex($i); $i++) {
    echo $entry['name'];
}
?>
Reflection
ReflectionFunction::isDisabled is deprecated, as it is no longer
     possible to create a ReflectionFunction for a disabled function. This
     method now always returns .
ReflectionParameter::getClass,
     ReflectionParameter::isArray, and
     ReflectionParameter::isCallable are deprecated.
     ReflectionParameter::getType and the
     ReflectionType APIs should be used instead.
New functions
Date and Time
DateTimeImmutable::createFromMutable
GMP
gmp_root
gmp_rootrem
Hash
hash_equals
LDAP
ldap_escape
ldap_modify_batch
MySQLi
mysqli_get_links_stats
OCI8
oci_get_implicit_resultset
OpenSSL
openssl_get_cert_locations
openssl_x509_fingerprint
openssl_spki_new
openssl_spki_verify
openssl_spki_export_challenge
openssl_spki_export
PostgreSQL
pg_connect_poll
pg_consume_input
pg_flush
pg_socket
PDO_PGSQL
PDO::pgsqlGetNotify
PDO::pgsqlGetPid
Session
session_abort
session_reset
Zip
ZipArchive::setPassword
New global constants
GD
IMG_WEBP (as of PHP 5.6.25)
LDAP
LDAP_ESCAPE_DN
LDAP_ESCAPE_FILTER
OpenSSL
OPENSSL_DEFAULT_STREAM_CIPHERS
STREAM_CRYPTO_METHOD_ANY_CLIENT
STREAM_CRYPTO_METHOD_ANY_SERVER
STREAM_CRYPTO_METHOD_TLSv1_0_CLIENT
STREAM_CRYPTO_METHOD_TLSv1_0_SERVER
STREAM_CRYPTO_METHOD_TLSv1_1_CLIENT
STREAM_CRYPTO_METHOD_TLSv1_1_SERVER
STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT
STREAM_CRYPTO_METHOD_TLSv1_2_SERVER
PostgreSQL
PGSQL_CONNECT_ASYNC
PGSQL_CONNECTION_AUTH_OK
PGSQL_CONNECTION_AWAITING_RESPONSE
PGSQL_CONNECTION_MADE
PGSQL_CONNECTION_SETENV
PGSQL_CONNECTION_SSL_STARTUP
PGSQL_CONNECTION_STARTED
PGSQL_DML_ESCAPE
PGSQL_POLLING_ACTIVE
PGSQL_POLLING_FAILED
PGSQL_POLLING_OK
PGSQL_POLLING_READING
PGSQL_POLLING_WRITING
OpenSSL changes in PHP 5.6.x
Stream wrappers now verify peer certificates and host names by default when using SSL/TLS
Certificate fingerprints
Support has been added for extracting and verifying certificate
   fingerprints. openssl_x509_fingerprint has been added
   to extract a fingerprint from an X.509 certificate, and two
   SSL stream context options have been
   added: capture_peer_cert to capture the peer's X.509
   certificate, and peer_fingerprint to assert that the
   peer's certificate should match the given fingerprint.
Default ciphers updated
The default ciphers used by PHP have been updated to a more secure list
   based on the
   Mozilla cipher recommendations,
   with two additional exclusions: anonymous Diffie-Hellman ciphers, and RC4.
This list can be accessed via the new
   OPENSSL_DEFAULT_STREAM_CIPHERS constant, and can be
   overridden (as in previous PHP versions) by setting the
   ciphers
   context option.
Compression disabled by default
SSL/TLS compression has been disabled by default to mitigate the CRIME
   attack. PHP 5.4.13 added a
   disable_compression
   context option to allow compression to be disabled: this is now set to
    (that is, compression is disabled) by default.
Allow servers to prefer their cipher order
The honor_cipher_order SSL context option has been
   added to allow encrypted stream servers to mitigate BEAST vulnerabilities
   by preferring the server's ciphers to the client's.
Access the negotiated protocol and cipher
The protocol and cipher that were negotiated for an encrypted stream can
   now be accessed via stream_get_meta_data or
   stream_context_get_options when the
   capture_session_meta SSL context option is set to
   .
New options for perfect forward secrecy in encrypted stream servers
Encrypted client streams already support perfect forward secrecy, as it is
   generally controlled by the server. PHP encrypted server streams using
   certificates capable of perfect forward secrecy do not need to take any
   additional action to enable PFS; however a number of new SSL context options
   have been added to allow more control over PFS and deal with any
   compatibility issues that may arise.
This option allows the selection of a specific curve for use with ECDH
      ciphers. If not specified, prime256v1 will be used.
A path to a file containing parametrs for Diffie-Hellman key exchange,
      such as that created by the following command:
If set to , a new key pair will be created when using
      Diffie-Hellman parameters, thereby improving forward secrecy.
If set to , a new key pair will always be generated when ECDH
      cipher suites are negotiated. This improves forward secrecy.
SSL/TLS version selection
It is now possible to select specific versions of SSL and TLS via the
   crypto_method SSL context option or by specifying a
   specific transport when creating a stream wrapper (for example, by calling
   stream_socket_client or
   stream_socket_server).
The crypto_method SSL context option accepts a
   bitmask enumerating the protocols that are permitted, as does the
   crypto_type of
   stream_socket_enable_crypto.
Selected protocol versions and corresponding options
openssl_get_cert_locations added
The openssl_get_cert_locations function has been
   added: it returns the default locations PHP will search when looking for
   CA bundles.
SPKI support
Support has been added for generating, extracting and verifying signed
   public key and challenges (SPKAC). openssl_spki_new,
   openssl_spki_verify,
   openssl_spki_export_challenge, and
   openssl_spki_export have been added to create, verify
   export PEM public key and associated challenge from
   SPKAC's generated from a KeyGen HTML5 element.
Generates a new SPKAC using private key, challenge string and hashing
      algorithm.
Verifies provided SPKAC.
Exports associated challenge from provided SPKAC.
Exports the PEM formatted RSA public key from SPKAC.
Backward incompatible changes
Although most existing PHP 5 code should work without changes, please take
  note of some backward incompatible changes:
Array keys won't be overwritten when defining an array as a property of a class via an array literal
Previously, arrays declared as class properties which mixed explicit and
   implicit keys could have array elements silently overwritten if an explicit
   key was the same as a sequential implicit key. For example:
json_decode strictness
json_decode now rejects non-lowercase variants of the
   JSON literals true, false and
   null at all times, as per the JSON specification, and
   sets json_last_error accordingly. Previously, inputs
   to json_decode that consisted solely of one of these
   values in upper or mixed case were accepted.
This change will only affect cases where invalid JSON was being passed to
   json_decode: valid JSON input is unaffected and will
   continue to be parsed normally.
Stream wrappers now verify peer certificates and host names by default when using SSL/TLS
GMP resources are now objects
GMP resources are now objects. The
   functional API implemented in the GMP extension has not changed, and code
   should run unmodified unless it checks explicitly for a resource using
   is_resource or similar.
Mcrypt functions now require valid keys and IVs
mcrypt_encrypt, mcrypt_decrypt,
   mcrypt_cbc, mcrypt_cfb,
   mcrypt_ecb, mcrypt_generic and
   mcrypt_ofb will no longer accept keys or IVs with
   incorrect sizes, and block cipher modes that require IVs will now fail if
   an IV isn't provided.
cURL file uploads
Uploads using the @file syntax now require CURLOPT_SAFE_UPLOAD to be set to
   . CURLFile should be used instead.
New features
Constant expressions
It is now possible to provide a scalar expression involving numeric and
   string literals and/or constants in contexts where PHP previously expected
   a static value, such as constant and property declarations and default
   function arguments.
It is also now possible to define a constant array using the
   const keyword:
Variadic functions via ...
Variadic functions can
   now be implemented using the ... operator, instead of
   relying on func_get_args.
Argument unpacking via ...
Arrays and
   Traversable objects can be unpacked into
   argument lists when calling functions by using the ...
   operator. This is also known as the splat operator in other languages,
   including Ruby.
Exponentiation via **
A right associative ** operator has been added to
   support exponentiation, along with a **= shorthand
   assignment operator.
use function and use const
The
   use 
   operator has been extended to support importing functions and constants in
   addition to classes. This is achieved via the
   use function and use const
   constructs, respectively.
phpdbg
PHP now includes an interactive debugger called phpdbg implemented as a
   SAPI module. For more information, please visit the
   phpdbg documentation.
Default character encoding
default_charset is now used as
   the default character set for the htmlentities,
   html_entity_decode and
   htmlspecialchars functions. Note that if the (now
   deprecated) iconv and mbstring encoding settings are set, they will take
   precedence over default_charset for iconv and mbstring functions,
   respectively.
The default value for this setting is UTF-8.
php://input is reusable
php://input
   may now be reopened and read as many times as required. This work has also
   resulted in a major reduction in the amount of memory required to deal
   with POST data.
Large file uploads
Files larger than 2 gigabytes in size are now accepted.
GMP supports operator overloading
GMP objects now support operator
   overloading and casting to scalar types. This allows for more expressive
   code using GMP:
hash_equals for timing attack safe string comparison
The hash_equals function has been added to compare
   two strings in constant time. This should be used to mitigate timing
   attacks; for instance, when testing crypt password
   hashes (assuming that you are unable to use
   password_hash and
   password_verify, which aren't susceptible to timing
   attacks).
__debugInfo()
The __debugInfo()
   magic method has been added to allow objects to change the properties and
   values that are shown when the object is output using
   var_dump.
gost-crypto hash algorithm
The gost-crypto hash algorithm has been added. This
   implements the GOST hash function using the CryptoPro S-box tables as
   specified by
   RFC 4357, section 11.2.
SSL/TLS improvements
A wide range of improvements have been made to the SSL/TLS support in PHP
   5.6. These include
   enabling peer verification by default,
   supporting certificate fingerprint matching, mitigating against TLS
   renegotiation attacks, and many new
   SSL context options to allow more fine
   grained control over protocol and verification settings when using
   encrypted streams.
These changes are described in more detail in the
   OpenSSL changes in PHP 5.6.x
   section of this migration guide.
pgsql async support
The pgsql extension now supports
   asynchronous connections and queries, thereby enabling non-blocking
   behaviour when interacting with PostgreSQL databases. Asynchronous
   connections may be established via the
   PGSQL_CONNECT_ASYNC constant, and the new
   pg_connect_poll, pg_socket,
   pg_consume_input and pg_flush
   functions may be used to handle asynchronous connections and queries.
Other changes to extensions
cURL
A number of constants marked obsolete in the cURL library have now been
   removed:
CURLOPT_CLOSEPOLICY
CURLCLOSEPOLICY_CALLBACK
CURLCLOSEPOLICY_LEAST_RECENTLY_USED
CURLCLOSEPOLICY_LEAST_TRAFFIC
CURLCLOSEPOLICY_OLDEST
CURLCLOSEPOLICY_SLOWEST
OCI8
Support for implicit result sets for Oracle Database 12c has been added
     via the new oci_get_implicit_resultset function.
Using oci_execute($s, OCI_NO_AUTO_COMMIT) for a
     SELECT no longer unnecessarily initiates an internal ROLLBACK during
     connection close.
Added DTrace probes controlled by the --enable-dtrace
     configure option.
oci_internal_debug is now a no-op.
The phpinfo output format for OCI8 has changed.
Zip
A --with-libzip configure option has been added to use
   a system libzip installation. libzip version 0.11 is required, with 0.11.2
   or later recommended.
MySQLi
A new mysqli.rollback_on_cached_plink
   option was added, which controls the rollback behavior of persistent connections.
Changed functions
PHP Core
crypt will now raise an
     E_NOTICE error if the salt
     parameter is omitted.
substr_compare will now accept 0
     for its length parameter.
unserialize will now fail if passed serialised data
     that has been manipulated to attempt to instantiate an object without
     calling its constructor.
cURL
Uploads using the @file syntax are now only supported
     if the CURLOPT_SAFE_UPLOAD option is set to
     . CURLFile should be used instead.
Mcrypt
The source parameter of
     mcrypt_create_iv now defaults to
     MCRYPT_DEV_URANDOM instead of
     MCRYPT_DEV_RANDOM.
OpenSSL
stream_socket_enable_crypto now allows the
     crypto_type parameter to be optional if the
     stream's SSL context includes the new crypto_type
     option.
PostgreSQL
pg_insert, pg_select,
     pg_update and pg_delete are no
     longer experimental.
pg_send_execute,
     pg_send_prepare, pg_send_query
     and pg_send_query_params will no longer block until
     query write completion if the underlying socket stream for the database
     connection is set to non-blocking mode.
Reflection
ReflectionClass::newInstanceWithoutConstructor
     now allows non-final internal classes to be
     instantiated.
XMLReader
XMLReader::getAttributeNs and
     XMLReader::getAttributeNo now return  if
     the attribute could not be found, like
     XMLReader::getAttribute.
Deprecated features in PHP 5.6.x
Calls from incompatible context
Methods called from an incompatible context are now deprecated, and will
   generate E_DEPRECATED errors when invoked instead of
   E_STRICT. Support for these calls will be removed in
   a future version of PHP.
An example of such a call is:
$HTTP_RAW_POST_DATA and always_populate_raw_post_data
always_populate_raw_post_data
   will now generate an E_DEPRECATED error when
   $HTTP_RAW_POST_DATA is populated.
   New code should use
   php://input
   instead of $HTTP_RAW_POST_DATA, which will be removed
   in a future release. You can opt in for the new behaviour (in which
   $HTTP_RAW_POST_DATA is never defined hence no
   E_DEPRECATED error will be generated) by setting
   always_populate_raw_post_data
   to -1.
iconv and mbstring encoding settings
The iconv and
   mbstring configuration options related
   to encoding have been deprecated in favour of
   default_charset.
   The deprecated options are:
iconv.input_encoding
iconv.output_encoding
iconv.internal_encoding
mbstring.http_input
mbstring.http_output
mbstring.internal_encoding
Windows Support
Support for long and UTF-8 path
If a web application is UTF-8 conform, no further action is required. For
    applications depending on paths in non UTF-8 encodings for I/O, an explicit
    INI directive has to be set. The encoding INI settings check relies on the
    order in the core:
internal_encoding
default_charset
zend.multibyte
Several functions for codepage handling were introduced:
sapi_windows_cp_set() to set the default codepage
sapi_windows_cp_get() to retrieve the current codepage
sapi_windows_cp_is_utf8()
sapi_windows_cp_conv() to convert between codepages, using iconv() compatible signature
These functions are thread safe.
The console output codepage is adjusted depending on the encoding used in
    PHP. Depending on the concrete system OEM codepage, the visible output
    might or might be not correct. For example, in the default cmd.exe and on
    a system with the OEM codepage 437, outputs in codepages 1251, 1252, 1253
    and some others can be shown correctly when using UTF-8. On the same system,
    chars in codepage like 20932 probably won't be shown correctly. This refers
    to the particular system rules for codepage, font compatibility and the
    particular console program used. PHP automatically sets the console codepage
    according to the encoding rules from php.ini. Using alternative consoles
    instead of cmd.exe directly might bring better experience in some cases.
Nevertheless be aware, runtime codepage switch after the request start
    might bring unexpected side effects on CLI. The preferable way is php.ini,
    When PHP CLI is used in a console emulator, that doesn't support Unicode,
    it might possibly be required, to avoid changing the console codepage. The
    best way to achieve it is by setting the default or internal encoding to
    correspond the ANSI codepage. Another method is to set the INI directives
    output_encoding and input_encoding to the required codepage, in which case
    however the difference between internal and I/O codepage is likely to cause
    mojibake. In rare cases, if PHP happens to crash gracefully, the original
    console codepage might be not restored. In this case, the chcp command
    can be used, to restore it manually.
Special awareness for the DBCS systems - the codepage switch on runtime
    using ini_set is likely to cause display issues. The difference to the
    non DBCS systems is, that the extended characters require two console cells
    to be displayed. In certain case, only the mapping of the characters into
    the glyph set of the font could happen, no actual font change. This is the
    nature of DBCS systems, the most simple way to prevent display issues is
    to avoid usage of ini_set for the codepage change.
As a result of UTF-8 support in the streams, PHP scripts are not limited
    to ASCII or ANSI filenames anymore. This is supported out of the box on
    CLI. For other SAPI, the documentation for the corresponding server
    is useful.
Long paths support is transparent. Paths longer than 260 bytes get
    automatically prefixed with \\?\. The max path length is limited to
    2048 bytes. Be aware, that the path segment limit (basename length) still
    persists.
For the best portability, it is strongely recommended to handle filenames,
    I/O and other related topics UTF-8. Additionally, for the console applications,
    the usage of a TrueType font is preferable and the usage of ini_set() for
    the codepage change is discouraged.
readline
The readline extension is supported
   through the WinEditLine
   library. Thereby, the interactive CLI shell is
   supported as well (php.exe -a).
PHP_FCGI_CHILDREN
PHP_FCGI_CHILDREN is now respected. If this environment variable is 
  defined, the first php-cgi.exe process will exec the specified number 
  of children. These will share the same TCP socket.
ftok()
Added support for ftok
New functions
PHP Core
sapi_windows_cp_get
sapi_windows_cp_set
sapi_windows_cp_conv
sapi_windows_cp_is_utf8
Closure
Closure::fromCallable
CURL
curl_multi_errno
curl_share_errno
curl_share_strerror
OpenSSL
openssl_get_curve_names
Session
session_create_id
session_gc
SPL
is_iterable
PCNTL
pcntl_async_signals
pcntl_signal_get_handler
New global constants
Core Predefined Constants
PHP_FD_SETSIZE
CURL
CURLMOPT_PUSHFUNCTION
CURL_PUSH_OK
CURL_PUSH_DENY
Data Filtering
FILTER_FLAG_EMAIL_UNICODE
Image Processing and GD
IMAGETYPE_WEBP
JSON
JSON_UNESCAPED_LINE_TERMINATORS
LDAP
LDAP_OPT_X_SASL_NOCANON
LDAP_OPT_X_SASL_USERNAME
LDAP_OPT_X_TLS_CACERTDIR
LDAP_OPT_X_TLS_CACERTFILE
LDAP_OPT_X_TLS_CERTFILE
LDAP_OPT_X_TLS_CIPHER_SUITE
LDAP_OPT_X_TLS_KEYFILE
LDAP_OPT_X_TLS_RANDOM_FILE
LDAP_OPT_X_TLS_CRLCHECK
LDAP_OPT_X_TLS_CRL_NONE
LDAP_OPT_X_TLS_CRL_PEER
LDAP_OPT_X_TLS_CRL_ALL
LDAP_OPT_X_TLS_DHFILE
LDAP_OPT_X_TLS_CRLFILE
LDAP_OPT_X_TLS_PROTOCOL_MIN
LDAP_OPT_X_TLS_PROTOCOL_SSL2
LDAP_OPT_X_TLS_PROTOCOL_SSL3
LDAP_OPT_X_TLS_PROTOCOL_TLS1_0
LDAP_OPT_X_TLS_PROTOCOL_TLS1_1
LDAP_OPT_X_TLS_PROTOCOL_TLS1_2
LDAP_OPT_X_TLS_PACKAGE
LDAP_OPT_X_KEEPALIVE_IDLE
LDAP_OPT_X_KEEPALIVE_PROBES
LDAP_OPT_X_KEEPALIVE_INTERVAL
PostgreSQL
PGSQL_NOTICE_LAST
PGSQL_NOTICE_ALL
PGSQL_NOTICE_CLEAR
SPL
MT_RAND_PHP
Backward incompatible changes
Throw on passing too few function arguments
Previously, a warning would be emitted for invoking user-defined functions
   with too few arguments. Now, this warning has been promoted to an Error
   exception. This change only applies to user-defined functions, not internal
   functions. For example:
Forbid dynamic calls to scope introspection functions
Dynamic calls for certain functions have been forbidden (in the form of
   $func() or array_map('extract', ...),
   etc). These functions either inspect or modify another scope, and present
   with them ambiguous and unreliable behavior. The functions are as follows:
assert - with a string as the first argument
compact
extract
func_get_args
func_get_arg
func_num_args
get_defined_vars
mb_parse_str - with one arg
parse_str - with one arg
Invalid class, interface, and trait names
The following names cannot be used to name classes, interfaces, or traits:
void
iterable
Numerical string conversions now respect scientific notation
Integer operations and conversions on numerical strings now respect
   scientific notation. This also includes the (int) cast
   operation, and the following functions: intval (where
   the base is 10), settype, decbin,
   decoct, and dechex.
Fixes to mt_rand algorithm
mt_rand will now default to using the fixed version of
   the Mersenne Twister algorithm. If deterministic output from
   mt_rand was relied upon, then
   MT_RAND_PHP can be used as optional second parameter
   to mt_srand to preserve the old (incorrect)
   implementation.
rand aliased to mt_rand and
   srand aliased to mt_srand
rand and srand have now been made
   aliases to mt_rand and mt_srand,
   respectively. This means that the output for the following functions have
   changed: rand, shuffle,
   str_shuffle, and array_rand.
Disallow the ASCII delete control character in identifiers
The ASCII delete control character (0x7F) can no longer
   be used in identifiers that are not quoted.
error_log changes with syslog
   value
If the error_log ini setting is set to
   syslog, the PHP error levels are mapped to the syslog
   error levels. This brings finer differentiation in the error logs in
   contrary to the previous approach where all the errors are logged with the
   notice level only.
Do not call destructors on incomplete objects
Destructors are now never called for objects that throw an exception during
   the execution of their constructor. In previous versions this behavior
   depended on whether the object was referenced outside the constructor (e.g.
   by an exception backtrace).
call_user_func handling of reference arguments
call_user_func will now always generate a warning
   upon calls to functions that expect references as arguments. Previously
   this depended on whether the call was fully qualified.
Additionally, call_user_func and
   call_user_func_array will no longer abort the function
   call in this case. The "expected reference" warning will be emitted, but the
   call will proceed as usual.
The empty index operator is not supported for strings anymore
Applying the empty index operator to a string (e.g. $str[] = $x)
   throws a fatal error instead of converting silently to array.
Assignment via string index access on an empty string
String modification by character on an empty string now works like for non-empty
   strings, i.e. writing to an out of range offset pads the string with spaces,
   where non-integer types are converted to integer, and only the first character of
   the assigned string is used. Formerly, empty strings where silently treated like
   an empty array.
   
    

<?php
$a = '';
$a[10] = 'foo';
var_dump($a);
?>

    
    
    

array(1) {
  [10]=>
  string(3) "foo"
}

    
    
    

string(11) "          f"
Removed ini directives
The following ini directives have been removed:
session.entropy_file
session.entropy_length
session.hash_function
session.hash_bits_per_character
Array ordering when elements are automatically created during by reference
   assignments has changed
The order of the elements in an array has changed when those elements have
   been automatically created by referencing them in a by reference
   assignment. For example:
Sort order of equal elements
The internal sorting algorithm has been improved, what may result in
   different sort order of elements, which compare as equal, than before.
Don't rely on the order of elements which compare as equal; it might change
    anytime.
Error message for E_RECOVERABLE errors
The error message for E_RECOVERABLE errors has been changed from "Catchable
   fatal error" to "Recoverable fatal error".
$options parameter of unserialize()
The allowed_classes element of the $options parameter of
   unserialize is now strictly typed, i.e. if anything
   other than an array or a bool is given,
   unserialize() returns  and issues an E_WARNING.
DateTime constructor incorporates microseconds
DateTime and DateTimeImmutable
   now properly incorporate microseconds when constructed from the current time,
   either explicitly or with a relative string (e.g. "first day of next
   month"). This means that naive comparisons of two newly created
   instances will now more likely return  instead of :
   
    

<?php
new DateTime() == new DateTime();
?>
Fatal errors to Error exceptions conversions
In the Date extension, invalid serialization data for
   DateTime or DatePeriod classes,
   or timezone initialization failure from serialized data, will now throw an
   Error exception from the
   __wakeup or __set_state
   methods, instead of resulting in a fatal error.
In the DBA extension, data modification functions (such as
   dba_insert) will now throw an
   Error exception instead of triggering a catchable
   fatal error if the key does not contain exactly two elements.
In the DOM extension, invalid schema or RelaxNG validation contexts will now
   throw an Error exception instead of resulting in a
   fatal error. Similarly, attempting to register a node class that does not
   extend the appropriate base class, or attempting to read an invalid property
   or write to a readonly property, will also now throw an
   Error exception.
In the IMAP extension, email addresses longer than 16385 bytes will throw an
   Error exception instead of resulting in a fatal error.
In the Intl extension, failing to call the parent constructor in a class
   extending Collator before invoking the parent methods
   will now throw an Error instead of resulting in a
   recoverable fatal error. Also, cloning a
   Transliterator object will now throw an
   Error exception on failure to clone the internal
   transliterator instead of resulting in a fatal error.
In the LDAP extension, providing an unknown modification type to
   ldap_batch_modify will now throw an
   Error exception instead of resulting in a fatal error.
In the mbstring extension, the mb_ereg and
   mb_eregi functions will now throw a
   ParseError exception if an invalid PHP expression is
   provided and the 'e' option is used.
In the Mcrypt extension, the mcrypt_encrypt and
   mcrypt_decrypt will now throw an
   Error exception instead of resulting in a fatal error
   if mcrypt cannot be initialized.
In the mysqli extension, attempting to read an invalid property or write to
   a readonly property will now throw an Error exception
   instead of resulting in a fatal error.
In the Reflection extension, failing to retrieve a reflection object or
   retrieve an object property will now throw an Error
   exception instead of resulting in a fatal error.
In the Session extension, custom session handlers that do not return strings
   for session IDs will now throw an Error exception
   instead of resulting in a fatal error when a function is called that must
   generate a session ID.
In the SimpleXML extension, creating an unnamed or duplicate attribute will
   now throw an Error exception instead of resulting in
   a fatal error.
In the SPL extension, attempting to clone an
   SplDirectory object will now throw an
   Error exception instead of resulting in a fatal
   error. Similarly, calling ArrayIterator::append when
   iterating over an object will also now throw an Error
   exception.
In the standard extension, the assert function, when
   provided with a string argument as its first parameter, will now throw a
   ParseError exception instead of resulting in a
   catchable fatal error if the PHP code is invalid. Similarly, calling
   forward_static_call outside of a class scope will now
   throw an Error exception.
In the Tidy extension, creating a tidyNode manually
   will now throw an Error exception instead of
   resulting in a fatal error.
In the WDDX extension, a circular reference when serializing will now throw
   an Error exception instead of resulting in a fatal
   error.
In the XML-RPC extension, a circular reference when serializing will now
   throw an instance of Error exception instead of
   resulting in a fatal error.
In the Zip extension, the ZipArchive::addGlob
   method will now throw an Error exception instead of
   resulting in a fatal error if glob support is not available.
Lexically bound variables cannot reuse names
Variables bound to a closure via
   the use construct cannot use the same name as any
   , $this, or any parameter. For
   example, all of these function definition will result in a fatal error:

   
    

<?php
$f = function () use ($_SERVER) {};
$f = function () use ($this) {};
$f = function ($param) use ($param) {};
long2ip() parameter type change
long2ip now expects an int instead of a
   string.
JSON encoding and decoding
The serialize_precision ini setting now controls the
   serialization precision when encoding floats.
Decoding an empty key now results in an empty property name, rather than 
   _empty_ as a property name.

   
   

<?php
var_dump(json_decode(json_encode(['' => 1])));

   
   
   

object(stdClass)#1 (1) {
  [""]=>
  int(1)
}
When supplying the JSON_UNESCAPED_UNICODE flag to
   json_encode, the sequences U+2028 and U+2029 are now
   escaped.
Changes to mb_ereg and mb_eregi
   parameter semantics
The third parameter to the mb_ereg and
   mb_eregi functions (regs) will now be
   set to an empty array if nothing was matched. Formerly, the parameter would
   not have been modified.
Drop support for the sslv2 stream
The sslv2 stream has now been dropped in OpenSSL.
Forbid "return;" for typed returns already at compile-time
Return statements without argument in functions which declare a return type
   now trigger E_COMPILE_ERROR (unless the return type is
   declared as void), even if the return statement would never be
   reached.
Other changes
Notices and warnings on arithmetic with invalid strings
New E_WARNING and E_NOTICE errors
   have been introduced when invalid strings are coerced using operators
   expecting numbers (+ -
   * / **
   % << >>
   | & ^) or their
   assignment equivalents. An E_NOTICE is emitted when the
   string begins with a numeric value but contains trailing non-numeric
   characters, and an E_WARNING is emitted when the string
   does not contain a numeric value.
Warn on octal escape sequence overflow
Previously, 3-octet octal string escape sequences would overflow silently.
   Now, they will still overflow, but E_WARNING will be
   emitted.
Inconsistency fixes to $this
Whilst $this is considered a special variable in PHP, it
   lacked proper checks to ensure it wasn't used as a variable name or
   reassigned. This has now been rectified to ensure that
   $this cannot be a user-defined variable, reassigned to a
   different value, or be globalised.
Session ID generation without hashing
Session IDs will no longer be hashed upon generation. With this change
   brings about the removal of the following four ini settings:
session.entropy_file
session.entropy_length
session.hash_function
session.hash_bits_per_character
And the addition of the following two ini settings:
session.sid_length - defines the length of the
     session ID, defaulting to 32 characters for backwards compatibility)
session.sid_bits_per_character - defines the number
     of bits to be stored per character (i.e. increases the range of characters
     that can be used in the session ID), defaulting to 4 for backwards
     compatibility
Changes to INI file handling
If the value is set to -1, then the dtoa mode 0 is used. The default
       value is still 14.
If the value is set to -1, then the dtoa mode 0 is used. The value -1 is
       now used by default.
The default of this  setting has been changed to 1, so by
       default libjpeg warnings are ignored.
The default of this  setting has been changed to 1
       (enabled) in PHP 7.1.2, and back to 0 (disabled) in PHP 7.1.7.
Session ID generation with a CSPRNG only
Session IDs will now only be generated with a CSPRNG.
More informative TypeError messages when  is allowed
TypeError exceptions for arg_info type checks will
   now provide more informative error messages. If the parameter type or return
   type accepts  (by either having a default value of  or being a
   nullable type), then the error message will now mention this with a message
   of "must be ... or null" or "must ... or be null."
New features
Nullable types
Type declarations for parameters and return values can now be marked as
   nullable by prefixing the type name with a question mark. This signifies
   that as well as the specified type,  can be passed as an argument, or
   returned as a value, respectively.
Void functions
A void return type has been introduced. Functions declared with
   void as their return type must either omit their return statement altogether,
   or use an empty return statement.  is not a valid return value for a
   void function.
Attempting to use a void function's return value simply evaluates to
   , with no warnings emitted. The reason for this is because warnings
   would implicate the use of generic higher order functions.
Symmetric array destructuring
The shorthand array syntax ([]) may now be used to
   destructure arrays for assignments (including within
   foreach), as an alternative to the existing
   list syntax, which is still supported.
Class constant visibility
Support for specifying the visibility of class constants has been added.
iterable pseudo-type
A new pseudo-type (similar to callable) called
   iterable has been introduced. It may be used in parameter
   and return types, where it accepts either arrays or objects that implement
   the Traversable interface. With respect to subtyping,
   parameter types of child classes may broaden a parent's declaration of array 
   or Traversable to iterable. With return types,
   child classes may narrow a parent's return type of iterable to
   array or an object that implements Traversable.
Multi catch exception handling
Multiple exceptions per catch block may now be specified using the pipe
   character (|). This is useful for when different
   exceptions from different class hierarchies are handled the same.
Support for keys in list
You can now specify keys in list, or its new shorthand
   [] syntax. This enables destructuring of arrays with
   non-integer or non-sequential keys.
Support for negative string offsets
Support for negative string offsets has been added to the
   string manipulation functions
   accepting offsets, as well as to
   string indexing with
   [] or {}. In such cases, a negative
   offset is interpreted as being an offset from the end of the string.
Negative string and array offsets are now also supported in the simple
   variable parsing syntax inside of strings.
Support for AEAD in ext/openssl
Support for AEAD (modes GCM and CCM) have been added by extending the
   openssl_encrypt and
   openssl_decrypt functions with additional parameters.
Convert callables to Closures with Closure::fromCallable
A new static method has been introduced to the Closure
   class to allow for callables to be easily converted into
   Closure objects.
Asynchronous signal handling
A new function called pcntl_async_signals has been
   introduced to enable asynchronous signal handling without using ticks (which
   introduce a lot of overhead).
HTTP/2 server push support in ext/curl
Support for server push has been added to the CURL extension (requires
   version 7.46 and above). This can be leveraged through the
   curl_multi_setopt function with the new
   CURLMOPT_PUSHFUNCTION constant. The constants
   CURL_PUSH_OK and CURL_PUSH_DENY have also been
   added so that the execution of the server push callback can either be
   approved or denied.
Stream Context Options
The tcp_nodelay stream
   context option has been added.
Changed functions
PHP Core
getopt has an optional third parameter that exposes
     the index of the next element in the argument vector list to be processed.
     This is done via a by-ref parameter.
getenv no longer requires its parameter. If the
     parameter is omitted, then the current environment variables will be
     returned as an associative array.
get_headers now has an additional parameter to enable
     for the passing of custom stream contexts.
output_reset_rewrite_vars no longer resets session
     URL rewrite variables.
parse_url is now more restrictive and supports
     RFC3986.
unpack now accepts an optional third parameter to
     specify the offset to begin unpacking from.
File System
file_get_contents now accepts a negative seek offset
     if the stream is seekable.
tempnam now emits a notice when falling back to the
     system's temp directory.
JSON
json_encode now accepts a new option,
     JSON_UNESCAPED_LINE_TERMINATORS, to disable the
     escaping of U+2028 and U+2029 characters when
     JSON_UNESCAPED_UNICODE is supplied.
Multibyte String
mb_ereg now rejects illegal byte sequences.
mb_ereg_replace now rejects illegal byte sequences.
PDO
PDO::lastInsertId for PostgreSQL will now trigger an error
     when nextval has not been called for the current
     session (the postgres connection).
PostgreSQL
pg_last_notice now accepts an optional parameter to
     specify an operation. This can be done with one of the following new
     constants: PGSQL_NOTICE_LAST,
     PGSQL_NOTICE_ALL, or
     PGSQL_NOTICE_CLEAR.
pg_fetch_all now accepts an optional second parameter
     to specify the result type (similar to the third parameter of
     pg_fetch_array).
pg_select now accepts an optional fourth parameter to
     specify the result type (similar to the third parameter of
     pg_fetch_array).
Session
session_start now returns  and no longer
     initializes $_SESSION when it failed to start the
     session.
Deprecated features in PHP 7.1.x
ext/mcrypt
The mcrypt extension has been abandonware for nearly a decade now, and was
   also fairly complex to use. It has therefore been deprecated in favour of
   OpenSSL, where it will be removed from the core and into PECL in PHP 7.2.
Eval option for mb_ereg_replace and mb_eregi_replace
The e pattern modifier has been deprecated for the
   mb_ereg_replace and
   mb_eregi_replace functions.
Windows Support
Core
The configuration variables PHP_VERSION,
   PHP_MINOR_VERSION, and
   PHP_RELEASE_VERSION are now always numbers.
   Previously, they have been strings for buildconf builds.
phpize builds now reflect the source tree in the
   build dir (as it already worked for in-tree builds); some extension
   builds (especially when using Makefile.frag.w32) may need adjustments.
--enable-sanitizer is now supported
   for MSVC builds.  This enables ASan and debug assertions, and is supported
   as of MSVC 16.10 and Windows 10.
The --with-uncritical-warn-choke
   configuration option for clang builds is no longer supported.
   Select warnings to suppress via CFLAGS instead.
COM
The extension is now build shared by default; previously it defaulted to a
   static extension, although the official Windows binaries built a shared
   extension.
FFI
It is no longer necessary to specify the library when using
   FFI::cdef and FFI::load.
   However, this convenience feature should not be used in production.
Streams
If only pipe streams are contained in the $read
   array, and the $write and
   $except arrays are empty,
   stream_select now behaves similar to POSIX systems,
   i.e. the function only returns if at least one pipe is ready to be read,
   or after the timeout expires.
   Previously, stream_select returned immediately,
   reporting all streams as ready to read.
New Classes and Interfaces
Core
Curl
Filter
URI
New Functions
Core
Curl
DOM
Enchant
Intl
Opcache
PDO_SQLITE
PGSQL
Reflection
Sqlite
Standard
New Global Constants
Core
cURL
Filter
Intl
OpenSSL
POSIX
Sockets
Tokenizer
Standard
Backward Incompatible Changes
PHP Core
"array" and "callable" alias name
It is no longer possible to use "array"
    and "callable" as class alias names
    in class_alias
Loosely comparing uncomparable objects
Loosely comparing uncomparable objects (e.g. enums,
    CurlHandle and other internal classes) to booleans
    was previously inconsistent. If compared to a boolean literal
    $object == true, it would behave the same way as
    (bool)$object. If compared to a statically unknown value
    $object == $true, it would always return .
    This behavior was consolidated to always follow the behavior of
    (bool)$object.
Return value of gc_collect_cycles
The return value of gc_collect_cycles no longer includes
    strings and resources that were indirectly collected through cycles.
Substitute static keyword in final subclass
It is now allowed to substitute static with self or the concrete class name
    in final subclasses.
Tick handlers
The tick handlers are now deactivated after all shutdown functions,
    destructors have run and the output handlers have been cleaned up.
Traits binding
Traits are now bound before the parent class. This is a subtle behavioral
    change, but should more closely match user expectations.
Errors during compilation and class linking
Errors emitted during compilation and class linking are now always delayed
    and handled after compilation or class linking. Fatal errors emitted during
    compilation or class linking cause any delayed errors to be handled
    immediately, without calling user-defined error handlers.
Exceptions thrown by user-defined error handler
Exceptions thrown by user-defined error handlers when handling class linking
    errors are not promoted to fatal errors anymore and do not prevent linking.
Attribute apply error during compilation
Applying #[\Attribute] to an abstract class, enum, interface, or trait
    triggers an error during compilation. Previously, the attribute could be
    added, but when ReflectionAttribute::newInstance
    was called an error would be thrown.
    The error can be delayed from compilation to runtime using the new
    #[\DelayedTargetValidation] attribute.
disable_classes INI setting
The disable_classes INI setting
    has been removed as it causes various engine assumptions to be broken.
Destructuring non-array values
Destructuring non-array values (other than ) using [] or list now
    emits a warning.
Warnings related to cast
A warning is now emitted when casting floats (or strings that look like
    floats) to int if they cannot be represented as one. This affects explicit
    int casts and implicit int casts.
A warning is now emitted when casting NAN to other types.
Bzip2
bzcompress now throws a ValueError
   when $block_size is not between 1 and 9.
bzcompress now throws a ValueError
   when $work_factor is not between 0 and 250.
DOM
Cloning a DOMNamedNodeMap,
   DOMNodeList, Dom\NamedNodeMap,
   Dom\NodeList, Dom\HTMLCollection,
   and Dom\DtdNamedNodeMap now fails.
   This never actually resulted in a working object, therefore no impact is expected.
FileInfo
finfo_file and finfo::file
   now throws a ValueError instead of a
   TypeError when $filename
   contains nul bytes.
   This aligns the type of Error thrown to be consistent with the rest of
   the language.
Intl
The extension now requires at least ICU 57.1.
IntlDateFormatter::setTimeZone/datefmt_set_timezone
   now throws an IntlException on uninitialised
   classes/clone failures.
All Locale methods now throw a
   ValueError when the locale argument contain null bytes.
The behaviour of Collator::SORT_REGULAR with respect to
   handling numeric strings is now aligned with the behaviour of
   SORT_REGULAR in ext/standard.
LDAP
ldap_get_option and ldap_set_option
   now throw a ValueError when passing an invalid option.
MBString
Unicode data tables have been updated to Unicode 17.0
MySQLi
Calling the mysqli constructor on an already-constructed object
   is now no longer possible and throws an Error.
ODBC
ODBC now assumes that at least ODBC 3.5 functionality is available.
   The ODBCVER definition and build system flags to control it have been removed.
ODBC no longer has build flags to build against specific drivers (except
   for DB2) and removes special cases for those drivers. It is strongly
   recommended to use a driver manager like iODBC or unixODBC on non-Windows.
Opcache
The Opcache extension is now always built into the PHP binary and is always
   loaded.
   The INI directives opcache.enable
   and opcache.enable_cli are still
   honored.
The --enable-opcache/--disable-opcache
   configure flags have been removed, and the build does not produce opcache.so
   or php_opcache.dll objects anymore.
Using zend_extension=opcache.so or
   zend_extension=php_opcache.dll INI directives
   will emit a warning.
PCNTL
pcntl_exec now throws ValueError
   when entries of the $args parameter contain null bytes.
pcntl_exec now throws ValueError
   when entries or keys of the $env_vars parameter
   contain null bytes.
PCRE
The extension is compiled without semi-deprecated
   PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK compile option.
PDO
The constructor arguments set in conjunction with
   PDO::FETCH_CLASS now follow the usual CUFA
   (call_user_func_array) semantics.
   This means string keys will act like a named argument.
   Moreover, automatic wrapping for by-value arguments passed to a by-ref
   parameter has been removed, and the usual E_WARNING
   about this is now emitted.
   To pass a variable by-ref to a constructor argument use the general
   array value reference assignment: $ctor_args = [$valByRef]
Attempting to call PDOStatement::setFetchMode during
   a call to PDO::fetch,
   PDO::fetchObject,
   PDO::fetchAll, for example using tricks such as
   passing the statement object as a constructor argument when fetching into an
   object, will now throw an Error.
The value of the constants PDO::FETCH_GROUP,
   PDO::FETCH_UNIQUE,
   PDO::FETCH_CLASSTYPE,
   PDO::FETCH_PROPS_LATE, and
   PDO::FETCH_SERIALIZE have changed.
A ValueError is now thrown if
   PDO::FETCH_PROPS_LATE is used with a fetch mode
   different than PDO::FETCH_CLASS, consistent with
   other fetch flags.
A ValueError is now thrown if
   PDO::FETCH_INTO is used as a fetch mode in
   PDO::fetchAll,
   similar to PDO::FETCH_LAZY.
PDO_FIREBIRD
A ValueError is now thrown when trying to set a cursor
   name that is too long on a PDOStatement resulting from
   the Firebird driver.
PDO_SQLITE
SQLite PDO::quote will now throw an exception
   or emit a warning, depending on the error mode, if the string contains
   a null byte.
PDO::sqliteCreateCollation will now throw an
   exception if the callback has the wrong return type, making it more
   in line with Pdo\Sqlite::createCollation behavior.
POSIX
posix_kill now throws a
   ValueError when the process_id argument is
   lower or greater than what the platform supports (signed integer or
   long range), posix_setpgid now throws a
   ValueError when the process_id or
   the process_group_id is lower than zero or greater than what the platform
   supports.
posix_setrlimit now throws a
   ValueError when the hard_limit or
   soft_limit arguments are lower than -1 or if soft_limit is greater than
   hard_limit.
Reflection
ReflectionAttribute::newInstance can now throw
   errors for internal attributes if the attribute was applied on an invalid
   target and the error was delayed from compile time to runtime via the
   #[\DelayedTargetValidation] attribute.
Session
Attempting to write session data where $_SESSION has a key
   containing the pipe character (|) will now emit a warning
   instead of silently failing.
session_start is stricter in regard to the options
   argument. It now throws a ValueError if
   the array is not a hashmap, or a TypeError
   if the read_and_close value is not a valid type compatible with int.
Passing an integer 0 as the locales
   argument to setlocale is no longer supported and now throws
   a TypeError.
SimpleXML
Passing an XPath expression that returns something other than a node set
   to SimpleXMLElement::xpath will now emit a warning
   and return , instead of silently failing and returning an empty array.
SNMP
snmpget,
   snmpset,
   snmp2_get,
   snmp2_set,
   snmp3_get,
   snmp3_set
   and SNMP::__construct now throw a
   ValueError when the hostname
   is too large, contains any null byte or if the port is given
   when negative or greater than 65535, timeout and retries values
   are lower than -1 or too large.
SOAP
SoapClient::__doRequest now accepts a new,
   optional $uriParserClass parameter accepting
   string or  arguments.
    represents the original (parse_url) based
   method, while the new backends will be used when passing either
   Uri\Rfc3986\Uri or Uri\WhatWg\Url.
Sockets
socket_create_listen,
   socket_bind and socket_sendto
   now throw a ValueError if the port is lower
   than 0 or greater than 65535, and also if any of the hints array entries are
   indexed numerically.
socket_addrinfo_lookup now throws a
   TypeError if any of the hints values cannot
   be cast to int and can throw a ValueError if
   any of these values overflow.
socket_set_option with
   MCAST_LEAVE_GROUP/MCAST_LEAVE_SOURCE_GROUP
   options now throw an exception if the value isn't a valid object or array.
socket_set_option with multicast context now throws a
   ValueError when the created socket is not of
   AF_INET/AF_INET6 family.
SPL
ArrayObject no longer accepts enums, as modifying the
   $name or $value properties can break
   engine assumptions.
SplFileObject::fwrite's parameter
   $length is now nullable.
   The default value changed from 0 to .
Standard
Using a printf-family function with a formatter that did not specify the
   precision previously incorrectly reset the precision instead of treating
   it as a precision of 0.
Tidy
tidy::__construct,
   tidy::parseFile,
   tidy::parseString now throws a
   ValueError if the configuration contains an
   invalid value or attempts to set a read-only internal entry,
   and a TypeError if a configuration key is not a
   string.
Other Changes
Core changes
Core
The high resolution timer (hrtime) on macOS now
    uses the recommended
    clock_gettime_nsec_np(CLOCK_UPTIME_RAW) API instead of
    mach_absolute_time().
CGI/CLI
The -z or --zend-extension option
    has been removed as it was non-functional.
    Use -d zend_extension=[path] instead.
PDO_ODBC
The fetch behaviour for larger columns has been changed. Rather than
    fetching 256 byte blocks, PDO_ODBC will try to fetch a larger block size;
    currently, this is the page size minus string overhead. Drivers that
    return SQL_NO_TOTAL in SQLGetData are also better handled as well.
    This should improve compatibility and performance.
Changes in SAPI Modules
CLI
Trying to set a process title that is too long with
    cli_set_process_title will now fail instead of
    silently truncating the given title.
Added a new --ini=diff option to print INI settings
    changed from the builtin default.
FPM
FPM with httpd ProxyPass optionally decodes the full script path. Added
    fastcgi.script_path_encoded
    INI setting to prevent this new behavior.
FPM access log limit now respects log_limit value.
Changed Functions
Intl
grapheme_extract properly assigns
    $next value when skipping over invalid starting bytes.
    Previously there were cases where it would point to the start of the
    grapheme boundary instead of the end.
transliterator_get_error_code,
    transliterator_get_error_message,
    TransLiterator::getErrorCode,
    and TransLiterator::getErrorMessage
    have dropped  from the return type union. Returning 
    was actually never possible.
The following functions now support a $locale argument:
    grapheme_strpos,
    grapheme_stripos,
    grapheme_strrpos,
    grapheme_strripos,
    grapheme_substr,
    grapheme_strstr and
    grapheme_stristr
LDAP
ldap_get_option now accepts a  connection,
    like ldap_set_option, to allow retrieval of global
    options.
libxml
libxml_set_external_entity_loader now has a formal
    return type of true.
OpenSSL
openssl_public_encrypt and
    openssl_private_decrypt have a new parameter
    $digest_algo that allows specifying the hash
    digest algorithm for OAEP padding.
openssl_sign and openssl_verify
    have a new parameter $padding to allow using more
    secure RSA PSS padding.
openssl_cms_encrypt $cipher_algo
    parameter can be a string with the cipher name.
    That allows to use more algorithms including AES GCM cipher algorithms for
    auth enveloped data.
PCNTL
pcntl_exec now has a formal return type of
    false.
pcntl_waitid takes an additional resource_usage
    argument to gather various platform specific metrics about the child process.
PDO_PGSQL
Pdo\Pgsql::copyFromArray now supports iterable inputs.
Pdo\Pgsql::setAttribute and
    Pdo\Pgsql::prepare support setting
    PDO::ATTR_PREFETCH to 0 which enters lazy fetch mode.
    In this mode, statements cannot be run in parallel.
PostgreSQL
pg_copy_from now supports iterable inputs.
pg_connect checks if the connection_string argument
    contains any null byte.
pg_close_stmt checks if the statement_name argument
    contains any null byte.
POSIX
posix_ttyname sets last_error to EBADF when encountering
    an invalid file descriptor.
posix_isatty raises an E_WARNING
    message when encountering an invalid file descriptor.
posix_fpathconf checks invalid file descriptors and
    sets last_error to EBADF and raises an E_WARNING message.
Reflection
The output of ReflectionClass::__toString for
    enums has changed to better indicate that the class is an enum, and that
    the enum cases are enum cases rather than normal class constants.
The output of ReflectionProperty::__toString for
    properties with hooks has changed to indicate what hooks the property has,
    whether those hooks are final, and whether the property is virtual.
    This also affects the output of ReflectionClass::__toString
    when a class contains hooked properties.
Sockets
socket_create/socket_bind can
    create AF_PACKET family sockets.
socket_getsockname gets the interface index and its
    string representation with AF_PACKET socket.
Zlib
The $use_include_path argument for the
    gzfile, gzopen and
    readgzfile functions has been changed
    from int to bool.
gzfile,
    gzopen and readgzfile functions
    now respect the default stream context.
Other Changes to Extensions
cURL
curl_setopt with
    CURLOPT_FOLLOWLOCATION option's value
    no longer is treated as boolean but integer to handle
    CURLFOLLOW_OBEYCODE and
    CURLFOLLOW_FIRSTONLY.
Fileinfo
Upgraded file from 5.45 to 5.46.
The return type of finfo_close has been changed to
    true, rather than bool.
Intl
Intl's internal error mechanism has been modernized so that it
    indicates more accurately which call site caused what error.
    Moreover, some ext/date exceptions have been wrapped inside a
    IntlException now.
Lexbor
An always enabled lexbor extension is added. It contains the lexbor
    library that was separated from ext/dom
    for being reused among other extensions.
    The new extension is not directly exposed to userland.
Opcache
The Opcache extension is now always
    built into the PHP binary and is always loaded.
    The INI directives opcache.enable
    and opcache.enable_cli are
    still honored.
PCRE
Upgraded pcre2lib from 10.44 to 10.46.
PDO_Sqlite
Increased minimum release version support from 3.7.7 to 3.7.17.
Readline
The return types of readline_add_history,
    readline_clear_history,
    and readline_callback_handler_install have been
    changed to true, rather than bool.
Reflection
ReflectionConstant is no longer final.
Changes to INI File Handling
Core
Added fatal_error_backtraces to control whether fatal errors should include
    a backtrace.
Added startup-only max_memory_limit INI setting to control the maximum
    memory_limit that may be configured at startup or runtime. Exceeding this
    value emits a warning, unless set to -1, and sets memory_limit to the
    current max_memory_limit instead.
Opcache
Added opcache.file_cache_read_only to support a read-only
    opcache.file_cache directory,
    for use with read-only file systems (e.g. read-only Docker containers).
    Best used with opcache.validate_timestamps=0,
    opcache.enable_file_override=1,
    and opcache.file_cache_consistency_checks=0.
A cache generated with a different build of PHP, a different file
     path, or different settings (including which extensions are loaded), may be
     ignored.
The default value of
    opcache.jit_hot_loop is
    now 61 (a prime) to prevent it from being a multiple of loop iteration
    counts.
    It is recommended that this parameter is set to a prime number.
Changing opcache.memory_consumption
    when OPcache SHM is already set up will now correctly report a failure
    instead of silently doing nothing and showing misleading values in PHPInfo.
OpenSSL
Added openssl.libctx
    to select the OpenSSL library context type.
    Either custom libctx for each thread can be used or a single global (default)
    libctx is used.
Performance
Core
Remove OPcodes for identity comparisons against booleans, particularly
    for the match(true) pattern.
Add OPcode specialization for === [] and
    !== [] comparisons.
Creating exception objects is now much faster.
The parts of the code that used SSE2 have been adapted to use SIMD
    with ARM NEON as well.
Introduced the TAILCALL VM, enabled by default when compiling with Clang>=19
    on x86_64 or aarch64. The TAILCALL VM is as fast as the HYBRID VM used when
    compiling with GCC. This makes PHP binaries built with Clang>=19 as fast as
    binaries built with GCC. The performance of the CALL VM, used with other
    compilers, has also improved considerably.
Intl
Now avoids creating extra string copies when converting strings
    for use in the collator.
MBString
The parts of the code that used SSE2 have been adapted to use SIMD
    with ARM NEON as well.
Opcache
Improved performance of fetching TLS variables in JIT'ed code in non-Glibc
    builds.
Reflection
Improved performance of the following methods:
    
     ReflectionProperty::getValue
     ReflectionProperty::getRawValue
     ReflectionProperty::isInitialized
     ReflectionProperty::isInitialized
     ReflectionProperty::setValue
     ReflectionProperty::setRawValue
SPL
Improved performance of dimension accessors and methods of
    SplFixedArray.
Standard
Improved performance of array functions with callbacks
    (array_find, array_filter,
    array_map, usort, ...).
Improved performance of urlencode and
    rawurlencode.
Improved unpack performance with nameless
    repetitions by avoiding creating temporary strings and reparsing them.
Improved pack performance.
Minor improvements in array_chunk performance.
XML
Improved XMLReader property access performance.
Improved XMLWriter performance and reduced memory
    consumption.
New Features
PHP Core
Pipe Operator
Added the pipe
    (|>) operator.
Closure in constant expressions
Added support for Closures and
    first class callables
    in constant expressions. This includes:

    
     Attribute parameters.
     Default values of properties and parameters.
     Constants and Class Constants.
#[\NoDiscard] attribute
Added the NoDiscard attribute to indicate that a
    function's return value is important and should be consumed.
Also, added the (void) cast to indicate that not using a value is intentional.
    The (void) cast has no effect on the program's execution by itself, but
    it can be used to suppress warnings emitted by #[\NoDiscard] and possibly
    also diagnostics emitted by external IDEs or static analysis tools.
Attributes on Constants
Added support for attributes on compile-time non-class constants
    (e.g. const MY_CONST = 1; rather than
    define('MY_CONST', 1);).
The Deprecated attribute can now be used on constants.
#[\DelayedTargetValidation] attribute
The new DelayedTargetValidation attribute can be used
    to suppress compile-time errors from core (or extension) attributes that are
    used on invalid targets. These errors are instead reported at runtime if and
    when ReflectionAttribute::newInstance is called.
#[\Override] for properties
Override attribute can now be applied to properties.
Static Asymmetric Visibility
Added asymmetric
    visibility support for static properties.
Backtraces for Fatal Errors
Fatal Errors (such as an exceeded maximum execution time) now include a
    backtrace.
Constructor promotion for final property
Constructor
    property promotion can now be used for final properties.
Casts in constant expressions
Added support for casts in constant expressions.
Clone function
The clone language construct
    is now a function and supports reassigning (readonly) properties during
    cloning via the new $withProperties parameter.
cURL
Added support for
   share handles
   that are persisted across multiple PHP requests, safely allowing for
   more effective connection reuse.
Added support for CURLINFO_USED_PROXY (libcurl >= 8.7.0),
   CURLINFO_HTTPAUTH_USED,
   and CURLINFO_PROXYAUTH_USED (libcurl >= 8.12.0)
   to the curl_getinfo function.
   When curl_getinfo returns an array, the same information
   is available as "used_proxy",
   "httpauth_used", and "proxyauth_used"
   keys.
   CURLINFO_USED_PROXY gets zero set if no proxy was used in the
   previous transfer or a non-zero value if a proxy was used.
   CURLINFO_HTTPAUTH_USED and
   CURLINFO_PROXYAUTH_USED get bitmasks
   indicating the HTTP and proxy authentication methods that were
   used in the previous request.
   See CURLAUTH_* constants for
   possible values.
Added CURLOPT_INFILESIZE_LARGE Curl option, which is a safe
   replacement for CURLOPT_INFILESIZE. On certain systems,
   CURLOPT_INFILESIZE only accepts a 32-bit signed integer as
   the file size (2.0 GiB) even on 64-bit systems.
   CURLOPT_INFILESIZE_LARGE accepts the largest integer value
   the system can handle.
Added CURLFOLLOW_OBEYCODE,
   CURLFOLLOW_FIRSTONLY and CURLFOLLOW_ALL
   values for CURLOPT_FOLLOWLOCATION
   curl_setopt option.
   CURLFOLLOW_OBEYCODE to follow more strictly in regard to
   redirect if they are allowed.
   CURLFOLLOW_FIRSTONLY to follow only the first redirect thus
   if there is any follow up redirect, it won't go any further.
   CURLFOLLOW_ALL is equivalent to setting
   CURLOPT_FOLLOWLOCATION to true.
Added support for CURLINFO_CONN_ID (libcurl >= 8.2.0)
   to the curl_getinfo function. This constant allows retrieving
   the unique ID of the connection used by a cURL transfer. It is primarily
   useful when connection reuse or connection pooling logic is needed in
   PHP-level applications. When curl_getinfo returns an array,
   this value is available as the "conn_id" key.
Added support for CURLINFO_QUEUE_TIME_T (libcurl >= 8.6.0)
   to the curl_getinfo function. This constant allows
   retrieving the time (in microseconds) that the request spent in libcurl’s
   connection queue before it was sent.
   This value can also be retrieved by passing
   CURLINFO_QUEUE_TIME_T to the curl_getinfo
   option parameter.
Added support for CURLOPT_SSL_SIGNATURE_ALGORITHMS to
   specify the signature algorithms to use for TLS.
DOM
Added Dom\Element::$outerHTML.
Added $children property to
   Dom\ParentNode implementations.
EXIF
Added support for OffsetTime* Exif tags.
Added support for HEIF/HEIC.
Filter
Added new FILTER_THROW_ON_FAILURE flag which can be
   passed to the filter functions and will force an exception to be triggered
   when validation fails.
   The new flag cannot be combined with
   FILTER_NULL_ON_FAILURE; trying to do so will result
   in a ValueError being thrown.
Intl
Added class constants NumberFormatter::CURRENCY_ISO,
   NumberFormatter::CURRENCY_PLURAL,
   NumberFormatter::CASH_CURRENCY,
   and NumberFormatter::CURRENCY_STANDARD
   for various currency-related number formats.
Added Locale::addLikelySubtags and
   Locale::minimizeSubtags to handle likely tags
   on a given locale.
Added IntlListFormatter class to format, order,
   and punctuate a list of items with a given locale,
   IntlListFormatter::TYPE_AND,
   IntlListFormatter::TYPE_OR,
   IntlListFormatter::TYPE_UNITS operands and
   IntlListFormatter::WIDTH_WIDE,
   IntlListFormatter::WIDTH_SHORT and
   IntlListFormatter::WIDTH_NARROW widths.
   It is supported from icu 67.
PDO_Sqlite
Added class constant Pdo\Sqlite::ATTR_BUSY_STATEMENT.
Added class constants Pdo\Sqlite::ATTR_EXPLAIN_STATEMENT,
   Pdo\Sqlite::EXPLAIN_MODE_PREPARED,
   Pdo\Sqlite::EXPLAIN_MODE_EXPLAIN,
   Pdo\Sqlite::EXPLAIN_MODE_EXPLAIN_QUERY_PLAN.
Added Pdo\Sqlite::ATTR_TRANSACTION_MODE connection attribute
   with possible values Pdo\Sqlite::TRANSACTION_MODE_DEFERRED,
   Pdo\Sqlite::TRANSACTION_MODE_IMMEDIATE,
   and Pdo\Sqlite::TRANSACTION_MODE_EXCLUSIVE,
   allowing to configure the transaction mode to use when calling beginTransaction().
Session
session_set_cookie_params,
   session_get_cookie_params,
   and session_start now support partitioned cookies via the
   "partitioned" key.
SOAP
Enumeration cases are now dumped in SoapClient::__getTypes.
Added support for Soap 1.2 Reason Text xml:lang attribute.
The signature of SoapFault::__construct and
   SoapServer::fault therefore
   now have an optional $lang parameter.
   This support solves compatibility with .NET SOAP clients.
Standard
mail now returns the actual sendmail error and detects
   if the sendmail process was terminated unexpectedly.
   In such cases, a warning is emitted and the function returns false.
   Previously, these errors were silently ignored.
   This change affects only the sendmail transport.
getimagesize now supports HEIF/HEIC images.
getimagesize now supports SVG images when ext-libxml
   is also loaded.
   Similarly, image_type_to_extension and
   image_type_to_mime_type
   now also handle IMAGETYPE_SVG.
The array returned by getimagesize now has two additional entries:
   "width_unit" and "height_unit" to indicate in
   which units the dimensions are expressed. These units are px by default. They are not
   necessarily the same (just to give one example: one may be cm and the other may be px).
setcookie and setrawcookie now support the
   "partitioned" key.
URI
An always enabled uri extension is added that can be used for handling
   URIs and URLs according to RFC 3986 and WHATWG URL.
XSL
The $namespace argument of XSLTProcessor::getParameter,
   XSLTProcessor::setParameter and
   XSLTProcessor::removeParameter now actually works
   instead of being treated as empty.
   This only works if the $name argument does not use Clark notation and is not a
   QName because in those cases the namespace is taken from the namespace href or
   prefix respectively.
Zlib
flock is now supported on zlib streams. Previously,
   this always failed to perform any locking action.
Deprecated Features
PHP Core
Changes to user output handler
Trying to produce output (e.g. with echo) within
    a user output handler is deprecated.
    The deprecation warning will bypass the handler producing the output to
    ensure it is visible; if there are nested output handlers the next
    one will still be used.
Non-canonical cast names
Non-canonical cast names (boolean),
    (integer), (double),
    and (binary) have been deprecated,
    use (bool), (int),
    (float), and (string) respectively.
Terminating case statements with a semicolon
Terminating case statements with a semicolon instead of a colon has
    been deprecated.
The backtick operator
The backtick operator
    as an alias for shell_exec has been deprecated.
Returning null from __debugInfo()
Returning  from
    __debugInfo()
    has been deprecated. Return an empty array instead.
report_memleaks INI directive
The report_memleaks INI directive
    has been deprecated.
Constant redeclaration
Constant redeclaration has been deprecated.
    Note that this already generated a warning and will continue to do so.
Closure binding issues
The following closure binding issues, which already emit an
    E_WARNING, are now deprecated:

    
     Binding an instance to a static closure.
     Binding methods to objects that are not instances of the class
      (or subclass) that the method is defined.
     Unbinding $this from a method.
     Unbinding $this from a closure that uses `$this`.
     Binding a closure to the scope of an internal class.
     Rebinding the scope of a closure created from a function or method.
__sleep() and __wakeup() magic methods
The __sleep() and
    __wakeup() magic methods
    have been soft-deprecated.
    The __serialize() and
    __unserialize() magic
    methods should be used instead, or at the same time if compatibility
    with PHP 7 is required.
Using null as an array offset
Using  as an array offset or when calling array_key_exists
    is now deprecated. Instead an empty string should be used.
Incrementing non-numeric strings
Incrementing non-numeric strings is now deprecated.
    Instead the str_increment function should be used.
register_argc_argv INI directive
Deriving $_SERVER['argc'] and $_SERVER['argv']
    from the query string for non-CLI SAPIs has been deprecated.
    Configure register_argc_argv=0 and switch to either
    $_GET or $_SERVER['QUERY_STRING']
    to access the information, after verifying that the usage is safe.
cURL
The curl_close function has been deprecated,
   as CurlHandle objects are freed automatically.
The curl_share_close function has been deprecated,
   as CurlShareHandle objects are freed automatically.
Date
The DATE_RFC7231 and
   DateTimeInterface::RFC7231 constants have been deprecated.
   This is because the associated timezone is ignored and always uses GMT.
FileInfo
The finfo_close function has been deprecated.
   As finfo objects are freed automatically.
The $context parameter of the
   finfo_buffer function has been deprecated
   as it is ignored.
GD
The imagedestroy function has been deprecated,
   as GdImage objects are freed automatically.
Hash
The MHASH_* constants have
   been deprecated.
Intl
The intl.error_level INI setting
   has been deprecated.
   Errors should either be checked manually or exceptions should be enabled by
   using the intl.use_exceptions
   INI setting.
LDAP
Specific Oracle Instant Client calls and constants have been deprecated.

   List of affected calls:
   
    ldap_connect with wallet support
    ldap_connect_wallet
   

   List of affected constants:
   
    GSLC_SSL_NO_UATH
    GSLC_SSL_ONEWAY_UATH
    GSLC_SSL_TWOWAY_UATH
MySQLi
The mysqli_execute alias function has been deprecated.
   Use mysqli_stmt_execute instead.
OpenSSL
The $key_length parameter for
   openssl_pkey_derive has been deprecated.
   This is because it is either ignored, or truncates the key, which can be
   a security vulnerability.
PDO
The "uri:" DSN scheme has been deprecated due to security concerns with
   DSNs coming from remote URIs.
Driver specific constants in the PDO class have been deprecated.
   List of affected constants and their replacement:

   
    PDO::DBLIB_ATTR_CONNECTION_TIMEOUT => Pdo\Dblib::ATTR_CONNECTION_TIMEOUT
    PDO::DBLIB_ATTR_QUERY_TIMEOUT => Pdo\Dblib::ATTR_QUERY_TIMEOUT
    PDO::DBLIB_ATTR_STRINGIFY_UNIQUEIDENTIFIER => Pdo\Dblib::ATTR_STRINGIFY_UNIQUEIDENTIFIER
    PDO::DBLIB_ATTR_VERSION => Pdo\Dblib::ATTR_VERSION
    PDO::DBLIB_ATTR_TDS_VERSION => Pdo\Dblib::ATTR_TDS_VERSION
    PDO::DBLIB_ATTR_SKIP_EMPTY_ROWSETS => Pdo\Dblib::ATTR_SKIP_EMPTY_ROWSETS
    PDO::DBLIB_ATTR_DATETIME_CONVERT => Pdo\Dblib::ATTR_DATETIME_CONVERT
    PDO::FB_ATTR_DATE_FORMAT => Pdo\Firebird::ATTR_DATE_FORMAT
    PDO::FB_ATTR_TIME_FORMAT => Pdo\Firebird::ATTR_TIME_FORMAT
    PDO::FB_ATTR_TIMESTAMP_FORMAT => Pdo\Firebird::ATTR_TIMESTAMP_FORMAT
    PDO::MYSQL_ATTR_USE_BUFFERED_QUERY => Pdo\Mysql::ATTR_USE_BUFFERED_QUERY
    PDO::MYSQL_ATTR_LOCAL_INFILE => Pdo\Mysql::ATTR_LOCAL_INFILE
    PDO::MYSQL_ATTR_LOCAL_INFILE_DIRECTORY => Pdo\Mysql::ATTR_LOCAL_INFILE_DIRECTORY
    PDO::MYSQL_ATTR_INIT_COMMAND => Pdo\Mysql::ATTR_INIT_COMMAND
    PDO::MYSQL_ATTR_MAX_BUFFER_SIZE => Pdo\Mysql::ATTR_MAX_BUFFER_SIZE
    PDO::MYSQL_ATTR_READ_DEFAULT_FILE => Pdo\Mysql::ATTR_READ_DEFAULT_FILE
    PDO::MYSQL_ATTR_READ_DEFAULT_GROUP => Pdo\Mysql::ATTR_READ_DEFAULT_GROUP
    PDO::MYSQL_ATTR_COMPRESS => Pdo\Mysql::ATTR_COMPRESS
    PDO::MYSQL_ATTR_DIRECT_QUERY => Pdo\Mysql::ATTR_DIRECT_QUERY
    PDO::MYSQL_ATTR_FOUND_ROWS => Pdo\Mysql::ATTR_FOUND_ROWS
    PDO::MYSQL_ATTR_IGNORE_SPACE => Pdo\Mysql::ATTR_IGNORE_SPACE
    PDO::MYSQL_ATTR_SSL_KEY => Pdo\Mysql::ATTR_SSL_KEY
    PDO::MYSQL_ATTR_SSL_CERT => Pdo\Mysql::ATTR_SSL_CERT
    PDO::MYSQL_ATTR_SSL_CA => Pdo\Mysql::ATTR_SSL_CA
    PDO::MYSQL_ATTR_SSL_CAPATH => Pdo\Mysql::ATTR_SSL_CAPATH
    PDO::MYSQL_ATTR_SSL_CIPHER => Pdo\Mysql::ATTR_SSL_CIPHER
    PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT => Pdo\Mysql::ATTR_SSL_VERIFY_SERVER_CERT
    PDO::MYSQL_ATTR_SERVER_PUBLIC_KEY => Pdo\Mysql::ATTR_SERVER_PUBLIC_KEY
    PDO::MYSQL_ATTR_MULTI_STATEMENTS => Pdo\Mysql::ATTR_MULTI_STATEMENTS
    PDO::ODBC_ATTR_USE_CURSOR_LIBRARY => Pdo\Odbc::ATTR_USE_CURSOR_LIBRARY
    PDO::ODBC_ATTR_ASSUME_UTF8 => Pdo\Odbc::ATTR_ASSUME_UTF8
    PDO::ODBC_SQL_USE_IF_NEEDED => Pdo\Odbc::SQL_USE_IF_NEEDED
    PDO::ODBC_SQL_USE_DRIVER => Pdo\Odbc::SQL_USE_DRIVER
    PDO::ODBC_SQL_USE_ODBC => Pdo\Odbc::SQL_USE_ODBC
    PDO::PGSQL_ATTR_DISABLE_PREPARES => Pdo\Pgsql::ATTR_DISABLE_PREPARES
    PDO::SQLITE_ATTR_EXTENDED_RESULT_CODES => Pdo\Sqlite::ATTR_EXTENDED_RESULT_CODES
    PDO::SQLITE_ATTR_OPEN_FLAGS => Pdo\Sqlite::OPEN_FLAGS
    PDO::SQLITE_ATTR_READONLY_STATEMENT => Pdo\Sqlite::ATTR_READONLY_STATEMENT
    PDO::SQLITE_DETERMINISTIC => Pdo\Sqlite::DETERMINISTIC
    PDO::SQLITE_OPEN_READONLY => Pdo\Sqlite::OPEN_READONLY
    PDO::SQLITE_OPEN_READWRITE => Pdo\Sqlite::OPEN_READWRITE
    PDO::SQLITE_OPEN_CREATE => Pdo\Sqlite::OPEN_CREATE
Driver specific methods in the PDO class have been deprecated.
   List of affected methods and their replacement:

   
    PDO::pgsqlCopyFromArray => Pdo\Pgsql::copyFromArray
    PDO::pgsqlCopyFromFile => Pdo\Pgsql::copyFromFile
    PDO::pgsqlCopyToArray => Pdo\Pgsql::copyToArray
    PDO::pgsqlCopyToFile => Pdo\Pgsql::copyToFile
    PDO::pgsqlGetNotify => Pdo\Pgsql::getNotify
    PDO::pgsqlGetPid => Pdo\Pgsql::getPid
    PDO::pgsqlLOBCreate => Pdo\Pgsql::lobCreate
    PDO::pgsqlLOBOpen => Pdo\Pgsql::lobOpen
    PDO::pgsqlLOBUnlink => Pdo\Pgsql::lobUnlink
    PDO::sqliteCreateAggregate => Pdo\Sqlite::createAggregate
    PDO::sqliteCreateCollation => Pdo\Sqlite::createCollation
    PDO::sqliteCreateFunction => Pdo\Sqlite::createFunction
PDO_PGSQL
Constants related to transaction states have been deprecated as this feature is unavailable with PDO:

   
    PDO::PGSQL_TRANSACTION_IDLE
    PDO::PGSQL_TRANSACTION_ACTIVE
    PDO::PGSQL_TRANSACTION_INTRANS
    PDO::PGSQL_TRANSACTION_INERROR
    PDO::PGSQL_TRANSACTION_UNKNOWN
Reflection
The setAccessible() methods of various Reflection objects have been
    deprecated, as those no longer have an effect.
Calling ReflectionClass::getConstant for constants
   that do not exist has been deprecated.
Calling ReflectionProperty::getDefaultValue for
   properties without default values has been deprecated.
SPL
Unregistering all autoloaders by passing the
   spl_autoload_call function as a callback argument to
   spl_autoload_unregister has been deprecated.
   Instead if this is needed, one should iterate over the return value of
   spl_autoload_functions and call
   spl_autoload_unregister on each value.
The SplObjectStorage::contains,
   SplObjectStorage::attach, and
   SplObjectStorage::detach methods have been deprecated
   in favour of SplObjectStorage::offsetExists,
   SplObjectStorage::offsetSet, and
   SplObjectStorage::offsetUnset respectively.
Using ArrayObject and
   ArrayIterator with objects has been deprecated.
Standard
The socket_set_timeout alias function has been deprecated.
   Use stream_set_timeout instead.
Passing  to readdir,
   rewinddir, and closedir
   to use the last opened directory has been deprecated.
   Provide the last opened directory explicitly instead.
Passing integers outside the interval [0, 255] to chr
   is now deprecated.
   This is because a byte can only hold a value within this interval.
Passing a string which is not a single byte to ord
   is now deprecated, this is indicative of a bug.
The locally predefined variable
   $http_response_header
   is deprecated. Instead one should call the
   http_get_last_response_headers function.
XML
The xml_parser_free function has been deprecated,
   as XMLParser objects are freed automatically.
Windows Support
Core
Windows specific error messages are no longer localized, but instead
   always displayed in English to better match PHP error messages.
Preliminary and highly experimental support for building on ARM64 has been added.
OCI8
Because building against Oracle Client 10g is no longer supported anyway,
   the configuration option --with-oci8 has been dropped.
   The --with-oci8-11g, --with-oci8-12c and
   --with-oci8-19 configuration options are still supported.
Zip
The Zip extension is upgraded to version 1.21.0,
   and is now built as shared library (DLL) by default.
New Functions
cURL
IMAP
MySQLi
ODBC
OpenSSL
Reflection
Sodium
XChaCha20
Standard
XML
New Global Constants
COM
DISP_E_PARAMNOTFOUND
LOCALE_NEUTRAL
cURL
CURLALTSVC_H1 (libcurl >= 7.64.1)
CURLALTSVC_H2 (libcurl >= 7.64.1)
CURLALTSVC_H3 (libcurl >= 7.64.1)
CURLALTSVC_READONLYFILE (libcurl >= 7.64.1)
CURLAUTH_AWS_SIGV4 (libcurl >= 7.75.0)
CURLE_PROXY (libcurl >= 7.73.0)
CURLFTPMETHOD_DEFAULT
CURLHSTS_ENABLE (libcurl >= 7.74.0)
CURLHSTS_READONLYFILE (libcurl >= 7.74.0)
CURLINFO_PROXY_ERROR (libcurl >= 7.73.0)
CURLINFO_REFERER (libcurl >= 7.76.0)
CURLINFO_RETRY_AFTER (libcurl >= 7.66.0)
CURLMOPT_MAX_CONCURRENT_STREAMS (libcurl >= 7.67.0)
CURLOPT_ALTSVC_CTRL (libcurl >= 7.64.1)
CURLOPT_ALTSVC (libcurl >= 7.64.1)
CURLOPT_AWS_SIGV4 (libcurl >= 7.75.0)
CURLOPT_CAINFO_BLOB (libcurl >= 7.77.0)
CURLOPT_DOH_SSL_VERIFYHOST (libcurl >= 7.76.0)
CURLOPT_DOH_SSL_VERIFYPEER (libcurl >= 7.76.0)
CURLOPT_DOH_SSL_VERIFYSTATUS (libcurl >= 7.76.0)
CURLOPT_HSTS_CTRL (libcurl >= 7.74.0)
CURLOPT_HSTS (libcurl >= 7.74.0)
CURLOPT_MAIL_RCPT_ALLLOWFAILS (libcurl >= 7.69.0)
CURLOPT_MAXAGE_CONN (libcurl >= 7.65.0)
CURLOPT_MAXFILESIZE_LARGE
CURLOPT_MAXLIFETIME_CONN (libcurl >= 7.80.0)
CURLOPT_PROXY_CAINFO_BLOB (libcurl >= 7.77.0)
CURLOPT_SASL_AUTHZID (libcurl >= 7.66.0)
CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256 (libcurl >= 7.80.0)
CURLOPT_SSL_EC_CURVES (libcurl >= 7.73.0)
CURLOPT_UPKEEP_INTERVAL_MS (libcurl >= 7.62.0)
CURLOPT_UPLOAD_BUFFERSIZE (libcurl >= 7.62.0)
CURLOPT_XFERINFOFUNCTION (libcurl >= 7.32.0)
CURLPROTO_MQTT (libcurl >= 7.71.0)
CURLPX_BAD_ADDRESS_TYPE (libcurl >= 7.73.0)
CURLPX_BAD_VERSION (libcurl >= 7.73.0)
CURLPX_CLOSED (libcurl >= 7.73.0)
CURLPX_GSSAPI (libcurl >= 7.73.0)
CURLPX_GSSAPI_PERMSG (libcurl >= 7.73.0)
CURLPX_GSSAPI_PROTECTION (libcurl >= 7.73.0)
CURLPX_IDENTD_DIFFER (libcurl >= 7.73.0)
CURLPX_IDENTD (libcurl >= 7.73.0)
CURLPX_LONG_HOSTNAME (libcurl >= 7.73.0)
CURLPX_LONG_PASSWD (libcurl >= 7.73.0)
CURLPX_LONG_USER (libcurl >= 7.73.0)
CURLPX_NO_AUTH (libcurl >= 7.73.0)
CURLPX_OK (libcurl >= 7.73.0)
CURLPX_RECV_ADDRESS (libcurl >= 7.73.0)
CURLPX_RECV_AUTH (libcurl >= 7.73.0)
CURLPX_RECV_CONNECT (libcurl >= 7.73.0)
CURLPX_RECV_REQACK (libcurl >= 7.73.0)
CURLPX_REPLY_ADDRESS_TYPE_NOT_SUPPORTED (libcurl >= 7.73.0)
CURLPX_REPLY_COMMAND_NOT_SUPPORTED (libcurl >= 7.73.0)
CURLPX_REPLY_CONNECTION_REFUSED (libcurl >= 7.73.0)
CURLPX_REPLY_GENERAL_SERVER_FAILURE (libcurl >= 7.73.0)
CURLPX_REPLY_HOST_UNREACHABLE (libcurl >= 7.73.0)
CURLPX_REPLY_NETWORK_UNREACHABLE (libcurl >= 7.73.0)
CURLPX_REPLY_NOT_ALLOWED (libcurl >= 7.73.0)
CURLPX_REPLY_TTL_EXPIRED (libcurl >= 7.73.0)
CURLPX_REPLY_UNASSIGNED (libcurl >= 7.73.0)
CURLPX_REQUEST_FAILED (libcurl >= 7.73.0)
CURLPX_RESOLVE_HOST (libcurl >= 7.73.0)
CURLPX_SEND_AUTH (libcurl >= 7.73.0)
CURLPX_SEND_CONNECT (libcurl >= 7.73.0)
CURLPX_SEND_REQUEST (libcurl >= 7.73.0)
CURLPX_UNKNOWN_FAIL (libcurl >= 7.73.0)
CURLPX_UNKNOWN_MODE (libcurl >= 7.73.0)
CURLPX_USER_REJECTED (libcurl >= 7.73.0)
CURLSSLOPT_AUTO_CLIENT_CERT (libcurl >= 7.77.0)
CURLSSLOPT_NATIVE_CA (libcurl >= 7.71.0)
CURLSSLOPT_NO_PARTIALCHAIN (libcurl >= 7.68.0)
CURLSSLOPT_REVOKE_BEST_EFFORT (libcurl >= 7.70.0)
CURL_VERSION_GSASL (libcurl >= 7.76.0)
CURL_VERSION_HSTS (libcurl >= 7.74.0)
CURL_VERSION_HTTP3 (libcurl >= 7.66.0)
CURL_VERSION_UNICODE (libcurl >= 7.72.0)
CURL_VERSION_ZSTD (libcurl >= 7.72.0)
DBA
DBA_LMDB_USE_SUB_DIR
DBA_LMDB_NO_SUB_DIR
Filter
FILTER_FLAG_GLOBAL_RANGE
Sockets
The following socket options are now defined if they are supported:
SO_INCOMING_CPU
SO_MEMINFO
SO_RTABLE (OpenBSD)
TCP_KEEPALIVE (MacOS)
TCP_KEEPCNT (Linux, others)
TCP_KEEPIDLE (Linux, others)
TCP_KEEPINTVL (Linux, others)
TCP_NOTSENT_LOWAT
LOCAL_CREDS_PERSISTENT (FreeBSD)
SCM_CREDS2 (FreeBSD)
LOCAL_CREDS (NetBSD)
SO_BPF_EXTENSIONS
SO_SETFIB
TCP_CONGESTION (Linux, FreeBSD)
SO_ZEROCOPY (Linux)
MSG_ZEROCOPY (Linux)
Backward Incompatible Changes
Date
DateTime::createFromImmutable now has a tentative
   return type of static, previously it was DateTime.
DateTimeImmutable::createFromMutable now has a tentative
   return type of static, previously it was DateTimeImmutable.
number symbols in relative formats
   no longer accept multiple signs, e.g. +-2.
ODBC
The ODBC extension now escapes the username and password for the case when
   both a connection string and username/password are passed, and the string
   must be appended to. Before, user values containing values needing escaping
   could have created a malformed connection string, or injected values from
   user-provided data. The escaping rules should be identical to the .NET BCL
   DbConnectionOptions behaviour.
PDO_ODBC
The PDO_ODBC extension also escapes the username and password when a
   connection string is passed. See the change to the ODBC extension for
   further details.
Standard
glob now returns an empty  if all paths are
   restricted by open_basedir.
   Previously it returned .
   Moreover, a warning is now emitted even if only some paths are restricted by
   open_basedir.
FilesystemIterator::__construct: prior to PHP 8.2.0,
   FilesystemIterator::SKIP_DOTS constant was always set
   and couldn't be disabled. In order to maintain the previous behaviour the constant
   must be explicitly set when using the flags parameter.
   The default value from flags parameter has
   not been modified.
strtolower,
   strtoupper,
   stristr,
   stripos,
   strripos,
   lcfirst,
   ucfirst,
   ucwords,
   and str_ireplace are no longer locale-sensitive.
   They now perform ASCII case conversion, as if the locale were "C".
   Localized versions of these functions are available in the MBString extension.
   Moreover, array_change_key_case, and sorting with
   SORT_FLAG_CASE now also use ASCII case conversion.
str_split returns an empty  for an empty  now.
   Previously it returned an array with a single empty string entry.
   mb_str_split is not affected by this change as it was
   already behaving like that.
ksort and krsort now do numeric string
   comparison under SORT_REGULAR using the standard PHP 8 rules now.
var_export no longer omits the leading backslash for exported classes,
   i.e. these are now fully qualified.
Standard PHP Library (SPL)
The following methods now enforce their signature:
   
    SplFileInfo::_bad_state_ex
    SplFileObject::getCsvControl
    SplFileObject::fflush
    SplFileObject::ftell
    SplFileObject::fgetc
    SplFileObject::fpassthru
SplFileObject::hasChildren now has a tentative
   return type of false, previously it was bool.
SplFileObject::getChildren now has a tentative
   return type of null, previously it was
   RecursiveIteratornull.
GlobIterator now returns an empty  if all
   paths are restricted by open_basedir.
   Previously it returned .
   Moreover, a warning is now emitted even if only some paths are restricted by
   open_basedir.
Other Changes
Core changes
The iterable type is now a built-in compile time alias for
   arrayTraversable.
   Error messages relating to iterable will therefore
   now use array|Traversable.
   Type Reflection is preserved for single iterable
   (and ?iterable) to produce a
   ReflectionNamedType with name iterable,
   however usage of iterable in union types will be
   converted to array|Traversable.
The date format of sent cookies is now 'D, d M Y H:i:s \G\M\T';
   previously it was 'D, d-M-Y H:i:s T'.
Changes in SAPI Modules
CLI
The STDOUT, STDERR and STDIN streams are no longer closed on resource destruction
    which is mostly when the CLI finishes. It is however still possible to
    explicitly close those streams using fclose and similar.
Changed Functions
Core
The strcmp, strcasecmp,
    strncmp, strncasecmp, and
    substr_compare functions, using binary safe string
    comparison is no longer guaranteed to return
    strlen($string1) - strlen($string2) when string lengths are not
    equal, but may now return -1 or 1
    instead. Instead of depending on any concrete value, the return value should
    be compared to 0.
DBA
dba_open and dba_popen
    now have the following enforced signature:
    
     resourcefalsedba_open
     stringpath
     stringmode
     stringnullhandler
     intpermission0644
     intmap_size0
     intnullflags
dba_fetch's optional skip argument is now at the end
    in line with PHP userland semantics. Its signature is now:
    
     stringfalsedba_fetch
     stringarraykey
     resourcehandle
     intskip
    

    The overloaded signature:
    
     stringfalsedba_fetch
     stringarraykey
     intskip
     resourcehandle
    
    is still accepted, but it is recommended to use the new standard variant.
Random
random_bytes and random_int
    now throw a \Random\RandomException on CSPRNG failures.
    Previously a plain \Exception was thrown instead.
SPL
The iterator parameter of
    iterator_to_array and iterator_count
    is widened to iterable from Iterator,
    allowing arrays to be passed.
Other Changes to Extensions
Date
The properties of DatePeriod are now properly declared.
Intl
Instances of
    IntlBreakIterator,
    IntlRuleBasedBreakIterator,
    IntlCodePointBreakIterator,
    IntlPartsIterator,
    IntlCalendar,
    Collator,
    IntlIterator,
    UConverter,
    IntlDateFormatter,
    IntlDatePatternGenerator,
    MessageFormatter,
    ResourceBundle,
    Spoofchecker,
    IntlTimeZone,
    and Transliterator
    are no longer serializable. Previously, they could be serialized, but
    unserialization yielded unusable objects or failed.
MySQLi
The support for libmysql has been removed and it is no longer
    possible to compile mysqli with libmysql.
    From now on, the mysqli extension can be compiled only with mysqlnd.
    All libmysql features unavailable in mysqlnd have been removed:
    
     The reconnect property of mysqli_driver
     
      The mysqli.reconnect INI directive
     
     The MYSQLI_IS_MARIADB constant has been deprecated
OCI8
The minimum Oracle Client library version required is now 11.2.
PCRE
NUL characters (\0) in pattern strings are now supported.
Session
Trying to change the
    session.cookie_samesite
    INI directive while the session is active or output has already been sent
    will now fail and emit a warning.
    This aligns the behaviour with all other session INI settings.
SQLite3
sqlite3.defensive
    is now INI_USER.
Standard
getimagesize now reports the actual image dimensions,
    bits and channels of AVIF images. Previously, the dimensions have been reported as 0x0,
    and bits and channels have not been reported at all.
Tidy
The properties of the tidy class are now properly declared.
    And those of the tidyNode class are now properly declared as readonly.
Zip
The Zip extension has been updated to version 1.20.0,
    which adds the following methods:
    
     ZipArchive::clearError
     ZipArchive::getStreamName
     ZipArchive::getStreamIndex
Changes to INI File Handling
Support for binary (0b/0B) and octal
   (0o/0O) prefixes has been added to integer INI settings.
   Integer INI settings that start with a zero (0)
   continue to be interpreted as an octal integer.
Parsing of some ill-formatted values will now trigger a warning when this
   was silently ignored before.
   For backwards compatibility, interpretation of these values has not changed.
   This affects the following settings:

   
    bcmath.scale
    com.code_page
    default_socket_timeout
    fiber.stack_size
    hard_timeout
    intl.error_level
    ldap.max_links
    max_input_nesting_level
    max_input_vars
    mbstring.regex_retry_limit
    mbstring.regex_stack_limit
    mysqli.allow_local_infile
    mysqli.allow_persistent
    mysqli.default_port
    mysqli.max_links
    mysqli.max_persistent
    mysqli.rollback_on_cached_plink
    mysqlnd.log_mask
    mysqlnd.mempool_default_size
    mysqlnd.net_read_buffer_size
    mysqlnd.net_read_timeout
    oci8.default_prefetch
    oci8.max_persistent
    oci8.persistent_timeout
    oci8.ping_interval
    oci8.prefetch_lob_size
    oci8.privileged_connect
    oci8.statement_cache_size
    odbc.allow_persistent
    odbc.check_persistent
    odbc.max_persistent
    odbc.max_links
    odbc.defaultbinmode
    odbc.default_cursortype
    odbc.defaultlrl
    opcache.consistency_checks
    opcache.file_update_protection
    opcache.force_restart_timeout
    opcache.interned_strings_buffer
    opcache.jit_bisect_limit
    opcache.jit_blacklist_root_trace
    opcache.jit_blacklist_side_trace
    opcache.jit_debug
    opcache.jit_hot_func
    opcache.jit_hot_loop
    opcache.jit_hot_return
    opcache.jit_hot_side_exit
    opcache.jit_max_exit_counters
    opcache.jit_max_loop_unrolls
    opcache.jit_max_polymorphic_calls
    opcache.jit_max_recursive_calls
    opcache.jit_max_recursive_returns
    opcache.jit_max_root_traces
    opcache.jit_max_side_traces
    opcache.log_verbosity_level
    opcache.max_file_size
    opcache.opt_debug_level
    opcache.optimization_level
    opcache.revalidate_freq
    output_buffering
    pcre.backtrack_limit
    pcre.recursion_limit
    pgsql.max_links
    pgsql.max_persistent
    post_max_size
    realpath_cache_size
    realpath_cache_ttl
    session.cache_expire
    session.cookie_lifetime
    session.gc_divisor
    session.gc_maxlifetime
    session.gc_probability
    soap.wsdl_cache_limit
    soap.wsdl_cache_ttl
    unserialize_max_depth
    upload_max_filesize
    user_ini.cache_ttl
    xmlrpc_error_number
    zend.assertions
    zlib.output_compression_level
New Features
PHP Core
SensitiveParameter Attribute
Added the #[\SensitiveParameter] attribute to redact
    sensitive data in backtraces.
error_log_mode INI directive
The error_log_mode INI directive has been added which allows setting
    the permissions for the error log file.
Enumerations properties in constant expressions
It is now possible to fetch properties of
    Enumerations
    in constant expressions.
Type System Improvements
It is now possible to use null and false
    as stand-alone types.
The true type has been added.
It is now possible to combine intersection and union types.
    The type needs to be written in DNF.
Constants in Traits
It is now possible to define constants in traits.
Readonly Classes
Support for readonly
    on classes has been added.
cURL
Added the CURLINFO_EFFECTIVE_METHOD option,
   which returns the effective HTTP method in the return value of
   curl_getinfo.
Exposed multiple new constants from libcurl 7.62 to 7.80.
Added the curl_upkeep function to perform any connection upkeep checks.
DBA
The LMDB Driver now accepts the DBA_LMDB_USE_SUB_DIR or
   DBA_LMDB_NO_SUB_DIR flags to determine if it should
   create a subdirectory or not when creating a database file.
OCI8
Added the oci8.prefetch_lob_size INI directive and
   oci_set_prefetch_lob function to tune LOB query
   performance by reducing the number of round-trips between PHP and
   Oracle Databases when fetching LOBS.
   This is usable with Oracle Database 12.2 or later.
OpenSSL
Added AEAD support for the chacha20-poly1305 algorithm.
ODBC
Added the odbc_connection_string_is_quoted,
   odbc_connection_string_should_quote, and
   odbc_connection_string_quote functions.
   These are primarily used behind the scenes in the ODBC and PDO_ODBC extensions,
   but are exposed to userland for easier unit testing, and for user
   applications and libraries to perform quoting themselves.
PCRE
Added support for the n (NO_AUTO_CAPTURE) modifier,
   which makes simple (xyz) groups non-capturing.
   Only named groups like (?<name>xyz) are capturing.
   This only affects which groups are capturing, it is still possible to use
   numbered subpattern references, and the matches array will still contain
   numbered results.
Random
This is a new extension which organises and consolidates existing
   implementations related to random number generators.
   New and better RNGs are available with scope issues eliminated.
Deprecated Features
PHP Core
Usage of dynamic properties
The creation of dynamic properties is deprecated, unless the class opts in by
    using the #[\AllowDynamicProperties] attribute.
    stdClass allows dynamic properties.
    Usage of the __get()/__set() magic methods is not affected by this change.
    A dynamic properties deprecation warning can be addressed by:

    
     Declaring the property (preferred).
     
      Adding the #[\AllowDynamicProperties] attribute to the class
      (which also applies to all child classes).
     
     
      Using a WeakMap if additional data needs to be
      associated with an object which one does not own.
Relative callables
Callables that are not accepted by the $callable() syntax
    (but are accepted by call_user_func) are deprecated.

    In particular:
    
     "self::method"
     "parent::method"
     "static::method"
     ["self", "method"]
     ["parent", "method"]
     ["static", "method"]
     ["Foo", "Bar::method"]
     [new Foo, "Bar::method"]
    

    This does not affect normal method callables such as
    "A::method" or ["A", "method"].
"${var}" and "${expr}" style interpolation
The "${var}" and "${expr}" style of string
    interpolation is deprecated.
    Use "$var"/"{$var}" and "{${expr}}", respectively.
MBString
Usage of the QPrint, Base64,
   Uuencode, and HTML-ENTITIES
   'text encodings' is deprecated for all MBString functions.

   Unlike all the other text encodings supported by MBString,
   these do not encode a sequence of Unicode codepoints, but rather a sequence of raw bytes.
   It is not clear what the correct return values for most MBString functions
   should be when one of these non-encodings is specified.
   Moreover, PHP has separate, built-in implementations of all of them;
   for example, UUencoded data can be handled using
   convert_uuencode/convert_uudecode.
SPL
The internal SplFileInfo::_bad_state_ex method
   has been deprecated.
Standard
utf8_encode and utf8_decode
   have been deprecated.
Windows Support
Core
Minimum supported Windows version has been bumped to Windows 8 or
   Windows Server 2012.
New Classes and Interfaces
Date
DateError
DateObjectError
DateRangeError
DateException
DateInvalidOperationException
DateInvalidTimeZoneException
DateMalformedIntervalStringException
DateMalformedPeriodStringException
DateMalformedStringException
Random
Random\IntervalBoundary
New Functions
Date
DOM
Intl
JSON
LDAP
MBString
Posix
PostgreSQL
Random
Reflection
Sockets
Standard
Zip
New Global Constants
cURL
CURLINFO_CAPATH (libcurl >= 7.84.0)
CURLINFO_CAINFO (libcurl >= 7.84.0)
CURLOPT_MIME_OPTIONS (libcurl >= 7.81.0)
CURLMIMEOPT_FORMESCAPE (libcurl >= 7.81.0)
CURLOPT_WS_OPTIONS (libcurl >= 7.86.0)
CURLWS_RAW_MODE (libcurl >= 7.86.0)
CURLOPT_SSH_HOSTKEYFUNCTION (libcurl >= 7.84.0)
CURLOPT_PROTOCOLS_STR (libcurl >= 7.85.0)
CURLOPT_REDIR_PROTOCOLS_STR (libcurl >= 7.85.0)
CURLOPT_CA_CACHE_TIMEOUT (libcurl >= 7.87.0)
CURLOPT_QUICK_EXIT (libcurl >= 7.87.0)
CURLKHMATCH_OK (libcurl >= 7.19.6)
CURLKHMATCH_MISMATCH (libcurl >= 7.19.6)
CURLKHMATCH_MISSING (libcurl >= 7.19.6)
CURLKHMATCH_LAST (libcurl >= 7.19.6)
Intl
MIXED_NUMBERS
    (Spoofchecker)
HIDDEN_OVERLAY
    (Spoofchecker)
OpenSSL
OPENSSL_CMS_OLDMIMETYPE
PKCS7_NOOLDMIMETYPE
PCNTL
SIGINFO
PDO_ODBC
PDO_ODBC_TYPE
Posix
POSIX_SC_ARG_MAX
POSIX_SC_PAGESIZE
POSIX_SC_NPROCESSORS_CONF
POSIX_SC_NPROCESSORS_ONLN
POSIX_PC_LINK_MAX
POSIX_PC_MAX_CANON
POSIX_PC_MAX_INPUT
POSIX_PC_NAME_MAX
POSIX_PC_PATH_MAX
POSIX_PC_PIPE_BUF
POSIX_PC_CHOWN_RESTRICTED
POSIX_PC_NO_TRUNC
POSIX_PC_ALLOC_SIZE_MIN
POSIX_PC_SYMLINK_MAX
Sockets
The following socket options are now defined if they are supported:
SO_ATTACH_REUSEPORT_CBPF (Linux)
SO_DETACH_BPF (Linux)
SO_DETACH_FILTER (Linux)
TCP_QUICKACK (Linux)
IP_DONTFRAG (FreeBSD)
IP_MTU_DISCOVER (Linux)
IP_PMTUDISC_DO (Linux)
IP_PMTUDISC_DONT (Linux)
IP_PMTUDISC_WANT (Linux)
IP_PMTUDISC_PROBE (Linux)
IP_PMTUDISC_INTERFACE (Linux)
IP_PMTUDISC_OMIT (Linux)
AF_DIVERT (FreeBSD)
SOL_UDPLITE
UDPLITE_RECV_CSCOV
UDPLITE_SEND_CSCOV
SO_RERROR (NetBSD)
SO_ZEROIZE (OpenBSD)
SO_SPLICE (OpenBSD)
TCP_REPAIR (Linux)
SO_REUSEPORT_LB (FreeBSD)
IP_BIND_ADDRESS_NO_PORT (Linux)
Zip
ZipArchive::ER_DATA_LENGTH (libzip >= 1.10)
ZipArchive::ER_NOT_ALLOWED (libzip >= 1.10)
ZipArchive::AFL_RDONLY (libzip >= 1.10)
ZipArchive::AFL_IS_TORRENTZIP (libzip >= 1.10)
ZipArchive::AFL_WANT_TORRENTZIP (libzip >= 1.10)
ZipArchive::AFL_CREATE_OR_KEEP_FILE_FOR_EMPTY_ARCHIVE
     (libzip >= 1.10)
ZipArchive::FL_OPEN_FILE_NOW
ZipArchive::LENGTH_TO_END as default value for
     ZipArchive::addFile and
     ZipArchive::replaceFile
ZipArchive::LENGTH_UNCHECKED (libzip >= 1.10)
Backward Incompatible Changes
PHP Core
Programs that were very close to overflowing the call stack
Programs that were very close to overflowing the call stack may now throw an
    Error when using more than
    zend.max_allowed_stack_size-zend.reserved_stack_size bytes of stack
    (fiber.stack_size-zend.reserved_stack_size for fibers).
Executing proc_get_status() multiple times
Executing proc_get_status multiple times will now always
    return the right value on POSIX systems. Previously, only the first call
    of the function returned the right value. Executing
    proc_close after proc_get_status
    will now also return the right exit code. Previously this would return
    -1.
    Internally, this works by caching the result on POSIX systems.
    If the previous behaviour is required, it is possible to check the
    "cached" key in the array returned by
    proc_get_status to check whether the result was cached.
Zend Max Execution Timers
Zend Max Execution Timers is now enabled by default for ZTS builds on
    Linux.
Uses of traits with static properties
Uses of traits with static properties will now redeclare static properties
    inherited from the parent class. This will create a separate static
    property storage for the current class. This is analogous to adding the
    static property to the class directly without traits.
Assigning a negative index to an empty array
Assigning a negative index $n to an empty array will now make sure that the
    next index is $n+1 instead of 0.
Class constant visibility variance check
Class constant visibility variance is now correctly checked when inherited
    from interfaces.
WeakMap entries whose key maps to itself
WeakMap entries whose key maps to itself (possibly
    transitively) may now be removed during cycle collection if the key is not
    reachable except by iterating over the WeakMap (reachability via iteration is
    considered weak).
    Previously, such entries would never be automatically removed.
Date
The DateTime extension has introduced Date extension specific exceptions
   and errors under the DateError and
   DateException hierarchies, instead of warnings and
   generic exceptions. This improves error handling, at the expense
   of having to check for errors and exceptions.
DOM
Calling DOMChildNode::after,
   DOMChildNode::before,
   DOMChildNode::replaceWith
   on a node that has no parent is now a no-op instead of a hierarchy
   exception, which is the behaviour demanded by the DOM specification.
Using the DOMParentNode
   and DOMChildNode methods without a document now
   works instead of throwing a DOM_HIERARCHY_REQUEST_ERR
   DOMException.
   This is in line with the behaviour demanded by the DOM specification.
Calling DOMDocument::createAttributeNS without specifying
   a prefix would incorrectly create a default namespace, placing the element
   inside the namespace instead of the attribute. This bug is now fixed.
DOMDocument::createAttributeNS would previously
   incorrectly throw a DOM_NAMESPACE_ERRNAMESPACE_ERR
   DOMException when the prefix was already used for a
   different URI. It now correctly chooses a different prefix when there's a
   prefix name conflict.
New methods and properties were added to some DOM classes.
   If a userland class inherits from these classes and declare a method or property
   with the same name, the declarations must be compatible. Otherwise, a typical
   compile error about incompatible declarations will be thrown.
   See the list of new features
   and new functions for
   a list of the newly implemented methods and properties.
FFI
C functions that have a return type of void now return  instead of
   returning the following object object(FFI\CData:void) { }
Opcache
The opcache.consistency_checks
   INI directive was removed. This feature was broken with the tracing JIT,
   as well as with inheritance cache, and has been disabled without a way to
   enable it since PHP 8.1.18 and PHP 8.2.5.
   Both the tracing JIT and inheritance cache may modify shm after the script
   has been persisted by invalidating its checksum. The attempted fix skipped
   over the modifiable pointers but was rejected due to complexity. For this
   reason, it was decided to remove the feature instead.
Phar
The type of Phar class constants are now declared.
Standard
The range function has had various changes:
   
    A TypeError is now thrown when passing objects,
    resources, or arrays as the boundary inputs.
    A more descriptive ValueError is thrown when
    passing 0 for $step.
    A ValueError is now thrown when using a
    negative $step for increasing ranges.
    If $step is a float that can be interpreted
    as an int, it is now done so.
    A ValueError is now thrown if any argument
    is infinity or NAN.
    An E_WARNING is now emitted if
    $start or $end is the empty
    string. The value continues to be cast to the value 0.
    An E_WARNING is now emitted if
    $start or $end has more than
    one byte, only if it is a non-numeric string.
    An E_WARNING is now emitted if
    $start or $end is cast to an
    integer because the other boundary input is a number.
    (e.g. range(5, 'z');).
    An E_WARNING is now emitted if
    $step is a float when trying to generate a range of
    characters, except if both boundary inputs are numeric strings (e.g.
    range('5', '9', 0.5); does not produce a warning).
    range now produce a list of characters if one
    of the boundary inputs is a string digit instead of casting the other input
    to int (e.g. range('9', 'A');).
   

   
    

<?php
range('9', 'A');  // ["9", ":", ";", "<", "=", ">", "?", "@", "A"], as of PHP 8.3.0
range('9', 'A');  // [9, 8, 7, 6, 5, 4, 3, 2, 1, 0], prior to PHP 8.3.0
?>
number_format now handles negative
   $decimals values by rounding
   $num to abs($decimals) digits before the
   decimal point. Previously, negative $decimals values
   were ignored.
The file flags error check now catches all invalid flags.
   Notably FILE_APPEND was previously silently accepted.
SNMP
The type of SNMP class constants are now declared.
Other Changes
Core changes
FFI
FFI::load is now allowed during preloading
    when opcache.preload_user
    is the current system user. Previously,
    calling FFI::load was not possible
    during preloading if the
    opcache.preload_user
    directive was set.
FPM
FPM CLI test now fails if the socket path is longer than supported by the OS.
Opcache
In the CLI and phpdbg SAPIs, preloading does not require the
    opcache.preload_user
    directive to be set anymore when running as root.
    In other SAPIs, this directive is required when running as root because
    preloading is done before the SAPI switches to an unprivileged user.
Streams
Blocking fread on a socket connection returns
    immediately if there are any buffered data instead of waiting for more data.
A memory stream no longer fails if the seek offset is past the end.
    Instead, the memory will be increased on the next write and the data between
    the old end and the offset is filled with zero bytes, similar to how files work.
stat access operations like
    file_exists and similar will now use real
    path instead of the actual stream path. This is consistent with stream
    opening.
Changes in SAPI Modules
CLI
The STDOUT, STDERR and
    STDIN streams are no longer closed on resource
    destruction which is mostly when the CLI finishes.
    It is however still possible to explicitly close those streams using
    fclose and similar.
Changed Functions
Core
gc_status has added the following 8 fields:

    
     "running" => bool
     "protected" => bool
     "full" => bool
     "buffer_size" => int
     "application_time" => float: Total application
     time, in seconds (including collector_time)
     "collector_time" => float: Time spent collecting
     cycles, in seconds (including destructor_time and free_time)
     "destructor_time" => float: Time spent executing
     destructors during cycle collection, in seconds
     "free_time" => float: Time spent freeing values
     during cycle collection, in seconds
class_alias now supports creating an alias of an
    internal class.
Setting open_basedir at runtime
    using ini_set('open_basedir', ...); no longer accepts paths
    containing the parent directory (..). Previously,
    only paths starting with .. were disallowed. This could
    easily be circumvented by prepending ./ to the path.
User exception handlers now catch exceptions during shutdown.
The resultant HTML of highlight_string and
    highlight_file has changed.
    Whitespace between outer HTML tags is removed. Newlines and spaces
    are no longer converted to HTML entities. The whole HTML is now wrapped in a
    <pre> tag. The outer <span>
    tag has been merged with the <code> tag.
Calendar
easter_date now supports years from 1970 to
    2,000,000,000 on 64-bit systems, previously it only supported years in the
    range from 1970 to 2037.
Curl
curl_getinfo now supports two new constants:
    CURLINFO_CAPATH and
    CURLINFO_CAINFO. If option is , the following
    two additional keys are present:
    "capath" and "cainfo".
DOM
Changed DOMCharacterData::appendData tentative
    return type to true.
DOMDocument::loadHTML,
    DOMDocument::loadHTMLFile, and
    DOMDocument::loadXML now have a tentative
    return type of bool. Previously, this was documented as having a return
    type of DOMDocument|bool, but, as of PHP 8.0.0,
    DOMDocument
    cannot be returned as it is no longer statically callable.
Gd
The signature of imagerotate has changed.
    The $ignore_transparent parameter has been removed,
    as it was ignored since PHP 5.5.0.
Intl
datefmt_set_timezone (and its alias
    IntlDateformatter::setTimeZone)
    now returns  on success, previously  was returned.
IntlBreakiterator::setText now returns 
    on failure, previously  was returned.
    It now returns  on success, previously  was returned.
IntlChar::enumCharNames is now returning a boolean.
    Previously it returned  on success and  on failure.
IntlDateFormatter::__construct throws an U_ILLEGAL_ARGUMENT_ERROR
    exception when an invalid locale had been set.
MBString
mb_strtolower and mb_convert_case
    implement conditional casing rules for the Greek letter sigma.
    For mb_convert_case,
    conditional casing only applies to MB_CASE_LOWER
    and MB_CASE_TITLE modes, not to
    MB_CASE_LOWER_SIMPLE and
    MB_CASE_TITLE_SIMPLE.
mb_decode_mimeheader interprets underscores in
    QPrint-encoded MIME encoded words as required by RFC 2047; they are
    converted to spaces.
    Underscores must be encoded as "=5F" in such MIME
    encoded words.
In rare cases, mb_encode_mimeheader will transfer-encode
    its input string where it would pass it through as raw ASCII in PHP 8.2.
mb_encode_mimeheader no longer drops NUL (zero)
    bytes when QPrint-encoding the input string.
    This previously caused strings in certain text encodings, especially
    UTF-16 and UTF-32, to be corrupted by mb_encode_mimeheader.
mb_detect_encoding's "non-strict" mode now behaves
    as described in the documentation.
    Previously, it would return  if the same byte (for example, the first
    byte) of the input string was invalid in all candidate encodings.
    More generally, it would eliminate candidate encodings from consideration
    when an invalid byte was seen, and if the same input byte eliminated all
    remaining encodings still under consideration, it would return .
    On the other hand, if all candidate encodings but one were eliminated
    from consideration, it would return the last remaining one without regard
    for how many encoding errors might be encountered later in the string.
    This is different from the behavior described in the documentation, which
    says: "If strict is set to false, the closest matching encoding will be
    returned."
mysqli
mysqli_fetch_object now raises a
    ValueError instead of an Exception
    when the $constructor_args argument is non empty with
    the class not having constructor.
mysqli_poll now raises a ValueError
    when neither the $read
    nor the $error arguments are passed.
mysqli_field_seek and
    mysqli_result::field_seek now specify the return
    type as true instead of bool.
ODBC
odbc_autocommit now accepts  for the
    $enable parameter.
    Passing  has the same behaviour as passing only 1 parameter,
    namely indicating if the autocommit feature is enabled or not.
PGSQL
pg_fetch_object now raises a
    ValueError instead of an Exception
    when the $constructor_args argument is non empty with
    the class not having constructor.
pg_insert now raises a ValueError
    instead of a E_WARNING when the table specified is invalid.
pg_insert and pg_convert raises
    a ValueError or a TypeError
    instead of a E_WARNING when the value/type of a field
    does not match properly with a PostgreSQL's type.
The $row parameter of
    pg_fetch_result,
    pg_field_prtlen, and
    pg_field_is_null is now nullable.
Random
Changed mt_srand and srand to
    not check the number of arguments to determine whether a random seed should
    be used. Passing  will generate a random seed, 0
    will use zero as the seed. The functions are now consistent with
    Random\Engine\Mt19937::__construct.
Reflection
Return type of ReflectionClass::getStaticProperties
    is no longer nullable.
Standard
E_NOTICEs emitted by unserialize
    have been promoted to E_WARNING.
unserialize now emits a new E_WARNING
    if the input contains unconsumed bytes.
array_pad is now only limited by the maximum number of
    elements an array can have. Before, it was only possible to add at most 1048576
    elements at a time.
strtok raises an E_WARNING in the
    case token is not provided when starting tokenization.
password_hash will now chain the underlying
    Random\RandomException
    as the ValueError's $previous
    Exception when salt generation fails.
If using an array as the $command
    for proc_open, it must now have at least one
    non empty element. Otherwise a ValueError
    is thrown.
proc_open returns  if $command
    array is invalid command instead of resource object that produces warning later.
    This was already the case for Windows but it is now also the case if a posix_spawn
    implementation is in use (most Linux, BSD and MacOS platforms). There are still
    some old platforms where this behavior is not changed as posix_spawn is not
    supported there.
array_sum and array_product now
    warn when values in the array cannot be converted to int/float.
    Previously arrays and objects where ignored whilst every other value was
    cast to int. Moreover, objects that define a numeric cast (e.g.
    GMP) are now casted instead of ignored.
The $decimals of number_format
    now properly handles negative integers.
    Rounding with a negative value for $decimals means
    that $num is rounded to $decimals
    significant digits before the decimal point.
    Previously negative $decimals were silently
    ignored and the number got rounded to zero decimal places.
A new $before_needle argument has been added to
    strrchr. It behaves like its counterpart in the
    strstr or stristr functions.
str_getcsv and fgetcsv now return
    an empty string instead of a string with a single null byte for the last field
    which only contains an unterminated enclosure.
Other Changes to Extensions
Core
Using the increment/decrement
    operators (++/--) on values of type
    bool now emit warnings.
    This is because it currently has no effect, but will behave like
    $bool += 1 in the future.
Using the decrement
    operator (--) on values of type null now emit warnings.
    This is because it currently has no effect, but will behave like
    $null -= 1 in the future.
Internal objects that implement an _IS_NUMBER cast but not a do_operator
    handler that overrides addition and subtraction now can be incremented
    and decrement as if one would do $o += 1 or $o -= 1
DOM
The DOM lifetime mechanism has been reworked such that implicitly removed
    nodes can still be fetched. Previously this resulted in an exception.
SQLite3
The SQLite3 class now throws
    SQLite3Exception (extends
    Exception) instead of Exception.
The SQLite error code is now passed in the exception error code instead of
    being included in the error message.
Changes to INI File Handling
The assert.* INI settings have been deprecated.
     This comprises the following INI settings:
     
      assert.active
      assert.bail
      assert.callback
      assert.exception
      assert.warning
     
     If the value of the setting is equal to the default value, no deprecation
     notice is emitted.
     The zend.assertions INI setting
     should be used instead.
zend.max_allowed_stack_size
    is a new INI directive to set the maximum allowed stack size.
    Possible values are 0 (detect the process or thread maximum stack size),
    -1 (no limit), or a positive number of bytes.
    The default is 0.
    When it is not possible to detect the process or thread maximum stack
    size, a known system default is used.
    Setting this value too high has the same effect as disabling the stack size limit.
    Fibers use
    fiber.stack_size
    as maximum allowed stack size.
    An Error is thrown when the process call stack exceeds
    zend.max_allowed_stack_size-zend.reserved_stack_size
    bytes, to prevent stack-overflow-induced segmentation faults, with
    the goal of making debugging easier.
    The stack size increases during uncontrolled recursions involving internal functions
    or the magic methods
    __toString(),
    __clone(),
    __sleep(),
    __destruct().
    This is not related to stack buffer overflows, and is not a security feature.
zend.reserved_stack_size
     is a new INI directive to set the reserved stack size, in bytes.
     This is subtracted from the max allowed stack size,
     as a buffer, when checking the stack size.
Performance
DOM
Looping over a DOMNodeList now uses caching. Therefore
    requesting items no longer takes quadratic time by default.
Getting text content from nodes now avoids an allocation, resulting in a
    performance gain.
DOMChildNode::remove now runs in O(1) performance.
Standard
The file flags error check is now about 7% faster.
SPL
RecursiveDirectoryIterator now performs less I/O
    when looping over a directory.
New Features
PHP Core
Readonly Amendments
Anonymous classes may now be marked as readonly.
Readonly properties can now be reinitialized during cloning.
Typed Class Constants
Class, interface, trait, and enum constants now support type declarations.
Closures created from magic methods
Closures created from magic methods can now accept named arguments.
The final modifier with a method from a trait
The final modifier may now be used when using a method from a trait.
Override Attribute
Added the #[\Override] attribute to check that a method exists in a parent
    class or implemented interface.
Fetch class constant dynamically syntax
Class constants can now be accessed dynamically using the
    C::{$name} syntax.
Static variable Initializers
Static variable initializers can now contain arbitrary expressions.
Fallback value syntax for ini variables
php.ini now supports fallback/default value syntax.
    
    
     

<?php
/*
On /path/to/user.ini contains the following settings:

listen = localhost:${DRUPAL_FPM_PORT:-9000}
*/

$user_ini = parse_ini_file('/path/to/user.ini');
echo $user_ini['listen']; // localhost:9000
CLI
It is now possible to lint multiple files.
DOM
Added properties DOMElement::$className
   and DOMElement::$id.
   These are not binary-safe at the moment because of underlying limitations
   of libxml2.
   This means that the property values will be cut off at a NUL byte.
Added properties DOMNode::$isConnected
   and DOMNameSpaceNode::$isConnected.
Added properties DOMNode::$parentElement
   and DOMNameSpaceNode::$parentElement.
FFI
It is now possible to assign FFI\CData to other FFI\CData.
   Meaning CData can now be assigned to structs and fields.
Opcache
opcache_get_status()['scripts'][n]['revalidate'] now contains
   a Unix timestamp of when the next revalidation of the scripts timestamp is
   due, dictated by the
   opcache.revalidate_freq
   INI directive.
POSIX
posix_getrlimit now takes an optional
   $resource parameter to allow fetching a single resource limit.
posix_isatty now raises type warnings for integers
   following the usual ZPP semantics.
posix_ttyname now raises type warnings for integers
   following the usual ZPP semantics and value warnings for invalid file
   descriptor integers.
Streams
Streams can now emit the STREAM_NOTIFY_COMPLETED
   notification. This was previously not implemented.
Deprecated Features
PHP Core
Saner Increment/Decrement operators
Using the increment
    operator (++) on empty, non-numeric,
    or non-alphanumeric strings is now deprecated.
    Moreover, incrementing non-numeric strings is soft deprecated.
    That means no E_DEPRECATED diagnostic is emitted,
    but this feature should not be used when producing new code.
    The new str_increment function should be used instead.
Using the decrement
    operator (--) on empty or non-numeric strings is now deprecated.
get_class()/get_parent_class() call without arguments
Calling get_class and get_parent_class
    without arguments is now deprecated.
DBA
Calling dba_fetch with $dba as
   the 3rd argument is now deprecated.
FFI
Calling FFI::cast, FFI::new,
   and FFI::type statically is now deprecated.
Intl
The U_MULTIPLE_DECIMAL_SEP*E*RATORS
   constant had been deprecated, using the
   U_MULTIPLE_DECIMAL_SEP*A*RATORS
   constant instead is recommended.
The NumberFormatter::TYPE_CURRENCY constant has been deprecated.
LDAP
Calling ldap_connect with separate
   $hostname and $port is
   deprecated.
MBString
Passing a negative $width to
   mb_strimwidth is now deprecated.
Phar
Calling Phar::setStub with a
   resource and a $length
   is now deprecated. Such calls should be replaced by:
   $phar->setStub(stream_get_contents($resource));
Random
The MT_RAND_PHP Mt19937 variant is deprecated.
Reflection
Calling ReflectionProperty::setValue with only one
   parameter is deprecated.
   To set static properties, pass  as the first parameter.
Standard
The assert_options function is now deprecated.
The ASSERT_ACTIVE, ASSERT_BAIL,
   ASSERT_CALLBACK, ASSERT_EXCEPTION,
   and ASSERT_WARNING constants have been deprecated.
The assert.* INI settings have been deprecated.
   See the
   Changes to INI File Handling
   page for further details.
SQLite3
Using exceptions is now preferred, warnings will be removed in the future.
   Calling SQLite3::enableExceptions(false) will trigger a
   deprecation warning in this version.
Zip
The ZipArchive::FL_RECOMPRESS constant is deprecated
   and will be removed in a future version of libzip.
Windows Support
Core
Building with Visual Studio now requires at least Visual Studio 2019.
   However, Visual Studio 2022 is recommended.
AVX(2) CPU support is now properly detected for MSVC builds.
Native AVX-512 builds are now supported via the
   --enable-native-intrinsics=avx512
   configure option.
New Classes, Enums, and Interfaces
Core
BCMath
DBA
DOM
ODBC
PCNTL
PDO_DBLIB
PDO_FIREBIRD
PDO_MYSQL
PDO_ODBC
PDO_PGSQL
PDO_SQLITE
Reflection
SOAP
Standard
New Functions
Core
BCMath
Date
DOM
Hash
Intl
MBString
Opcache
PCNTL
PDO_PGSQL
PGSQL
Reflection
The following methods relate to the new lazy object feature:
   
    
     ReflectionClass::newLazyGhost
    
    
     ReflectionClass::newLazyProxy
    
    
     ReflectionClass::resetAsLazyGhost
    
    
     ReflectionClass::resetAsLazyProxy
    
    
     ReflectionClass::isUninitializedLazyObject
    
    
     ReflectionClass::initializeLazyObject
    
    
     ReflectionClass::markLazyObjectAsInitialized
    
    
     ReflectionClass::getLazyInitializer
    
    
     ReflectionProperty::skipLazyInitialization
    
    
     ReflectionProperty::setRawValueWithoutLazyInitialization
Sodium
SPL
SOAP
Standard
Tidy
XMLReader
XMLWriter
XSL
Removed Extensions
These extensions have been moved to PECL and are no longer part of the PHP
  distribution. New releases for the PECL packages will be published on an
  ad-hoc basis according to user demand.
New Global Constants
Core
cURL
Intl
LDAP
libxml
MySQLi
OpenSSL
PCNTL
PGSQL
POSIX
Sockets
The following socket options are now defined if they are supported:
Sodium
Tokenizer
XML
Backward Incompatible Changes
Although not explicitly stated in this section,
  every new function,
  class, interface, enum,
  or constant
  may cause a redeclaration Error to be thrown.
PHP Core
exit behavioral change
The exit (and die) language
    constructs now behave more like a function.
    This means that they can now be passed like callables,
    
    are affected by the strict_types declare statement,
    and now perform the usual type coercions instead of casting any non-integer
    value to a string.
As such, passing invalid types to exit and
    die now consistently result in a
    TypeError being thrown.
Recursion during comparison
Encountering recursion during comparison now results in an
    Error exception instead of a
    E_ERROR fatal error.
Indirect Modification of readonly Properties
Indirect modification of readonly properties within __clone()
    is no longer allowed, e.g. $ref = &$this->readonly.
    This was already forbidden for readonly initialization, and was an
    oversight in the "readonly reinitialization during cloning" implementation.
Type Change of Constants
The PHP_DEBUG and PHP_ZTS
    constants are now of type bool.
    Previously they were of type int.
Temporary Filename Length
The name of uploaded files and files created by the
    tempnam function are now 13 bytes longer.
    The total length is still platform-dependent.
Removal of E_STRICT error level
The E_STRICT error level has been removed,
    as it was no longer in use within the PHP engine.
    The E_STRICT constant has been deprecated.
Extension Class Constants which are now Typed
The following extension class constants now declare a type on their
   constants:
   
    Date
    Intl
    PDO
    Reflection
    SPL
    Sqlite
    XMLReader
Resource to Object Migration
Several s have been migrated to s.
   Return value checks using is_resource should be
   replaced with checks for , unless specified otherwise.
DBA
The DBA functions now accept and return
    Dba\Connection objects instead of
    dba_connection s.
ODBC
The ODBC functions now accept and return
    Odbc\Result objects instead of
    odbc_result s.
The ODBC functions now accept and return
    Odbc\Connection objects instead of
    odbc_connection s.
SOAP
The SoapClient::$httpurl property is now a
    Soap\Url object rather than a
    soap_url .
    Checks using is_resource (i.e.
    is_resource($client->httpurl)) should be  replaced with checks
    for  (i.e. $client->httpurl !== null).
The SoapClient::$sdl property is now a
    Soap\Sdl object rather than a
    soap_sdl .
    Checks using is_resource (i.e.
    is_resource($client->sdl)) should be  replaced with checks
    for  (i.e. $client->sdl !== null).
New warnings and exceptions
New warnings and exceptions have been added which are triggered on
   programming errors, i.e. invalid values provided as arguments.
Curl
curl_multi_select now throws a
    ValueError if the
    timeout parameter is less than
    0 or greater than PHP_INT_MAX.
Gd
imagejpeg
     imagewebp
     imagepng
     imageavif
    
    now throw a ValueError when an invalid
    quality is passed.
imageavif will now throw a
    ValueError if an invalid
    speed parameter value is passed.
imagescale will now throw a
    ValueError if the
    width or height
    parameters underflows/overflows.
imagescale will now throw a
    ValueError if an invalid
    mode parameter value is passed.
imagefilter will now throw a
    ValueError with the
    IMG_FILTER_SCATTER filter
    if the sub or plus
    parameters underflows/overflows.
Gettext
bind_textdomain_codeset
     textdomain
     d*gettext
    
    now throw a ValueError if
    domain is the empty string.
Intl
resourcebundle_get,
    ResourceBundle::get, and accessing offsets on
    a ResourceBundle object now throw:
    
     
      TypeError for invalid offset types
     
     
      ValueError for an empty 
     
     
      ValueError if the integer index does
      not fit in a signed 32 bit integer
IntlDateFormatter::__construct throws a
    ValueError if the
    locale is invalid.
NumberFormatter::__construct throws a
    ValueError if the
    locale is invalid.
MBString
mb_encode_numericentity and
    mb_decode_numericentity now check that the
    map is only composed of s,
    if not a ValueError is now thrown.
mb_http_input now always throw a
    ValueError if type
    is invalid.
mb_http_output now check that the
    encoding does not contain any null bytes,
    if it does a ValueError is now thrown.
ODBC
odbc_fetch_row returns  when
    row is less than or equal to 0.
    A warning is now emitted in this case.
PCNTL
The pcntl_sigprocmask,
    pcntl_sigwaitinfo, and
    pcntl_sigtimedwait functions now throw:
    
     
      A ValueError if the
      signals array is empty
      (except for pcntl_sigprocmask if the
      mode SIG_SETMASK)
     
     
      A TypeError if a value of the
      signals array is not an 
     
     
      A ValueError if a value of the
      signals array is not a valid signal number
The pcntl_sigprocmask function now throws a
    ValueError if the
    mode is not one of SIG_BLOCK,
    SIG_UNBLOCK, or SIG_SETMASK.
The pcntl_sigtimedwait function now throw:
    
     
      A ValueError if
      seconds is less than 0
     
     
      A ValueError if
      nanoseconds is less than 0
      or greater than 1e9
     
     
      A ValueError if both
      seconds and nanoseconds
      are 0
Session
Setting a non-positive value for session.gc_divisor
    or a negative value for session.gc_probability
    now emits a warning.
SimpleXML
Calling simplexml_import_dom with a non-XML object
    now throws a TypeError instead of a
    ValueError.
Standard
The round function now validates the value of the
    mode and throw a
    ValueError for invalid modes.
    Previously, invalid modes would have been interpreted as
    PHP_ROUND_HALF_UP.
The str_getcsv now throws
    ValueErrors when the
    separator and enclosure
    arguments are not one byte long, or if the escape
    argument is not one byte long nor the empty string.
    This aligns the behaviour to be identical to the one of
    fputcsv and fgetcsv.
The php_uname function now throws a
    ValueError if the
    mode is invalid.
The "allowed_classes" option for
    unserialize now throws
    TypeErrors and
    ValueErrors if it is not an
    array of class names.
XMLReader
Passing an invalid character encoding to
    XMLReader::open or
    XMLReader::XML now throws a
    ValueError.
Passing a  containing null bytes previously emitted a
    warning and now throws a ValueError.
XMLWriter
Passing a  containing null bytes previously emitted a
    warning and now throws a ValueError.
XSL
XSLTProcessor::setParameter will now throw a
    ValueError when its arguments contain null
    bytes. This never actually worked correctly in the first place,
    which is why it throws an exception now.
Calling XSLTProcessor::importStyleSheet with a
    non-XML object now throws a TypeError
    instead of a ValueError.
Failure to call a PHP function callback during evaluation now throws
    instead of emitting a warning.
Date
number symbols in relative formats
   once again accept multiple signs, e.g. +-2.
DOM
Some DOM methods previously returned  or a
   DOMException with code
   DOM_PHP_ERR if a new node could not be allocated.
   They now consistently throw a DOMException
   with code DOM_INVALID_STATE_ERR.
   This situation is extremely unlikely and the probability of being affected
   is low.
   As a result DOMImplementation::createDocument
   now has a tentative return type of DOMDocument
   
   instead of DOMDocument|false.
Previously, DOMXPath objects could be cloned,
   but resulted in an unusable object.
   This is no longer possible, and cloning a DOMXPath
   object now throws an Error.
The DOMImplementation::getFeature method has been removed.
GMP
The GMP class is now final and cannot be extended
   anymore.
MBString
On invalid strings (those with encoding errors),
   mb_substr now interprets character indices in the same
   manner as most other mbstring functions.
   This means that character indices returned by mb_strpos
   can be passed to mb_substr.
For SJIS-Mac (MacJapanese) strings, character indices passed to
   mb_substr now refer to the indices of the Unicode
   codepoints which are produced when the string is converted to Unicode.
   This is significant because around 40 SJIS-Mac characters convert to a
   sequence of multiple Unicode codepoints.
MySQLi
The unused and undocumented constant
   MYSQLI_SET_CHARSET_DIR has been removed.
The MYSQLI_STMT_ATTR_PREFETCH_ROWS constant has been
   removed. The feature is unavailable with mysqlnd.
The MYSQLI_CURSOR_TYPE_FOR_UPDATE and
   MYSQLI_CURSOR_TYPE_SCROLLABLE constants have been
   removed. This functionality was never implemented,
   neither with mysqlnd nor with libmysql.
The unused MYSQLI_TYPE_INTERVAL constant, which is
   currently a stub and an alias for MYSQLI_TYPE_ENUM,
   has been removed.
MySQLnd
The error code reported for MySQL server wait timeouts has been changed from
   2006 to 4031 for MySQL server
   versions 8.0.24 and above.
Opcache
The maximum value of the
   opcache.interned_strings_buffer
   setting on 64bit architectures is now 32767.
   Previously it was 4095.
JIT
The default configuration values for the JIT changed from
    opcache.jit=tracing
    and opcache.jit_buffer_size=0
    to opcache.jit=disable
    and opcache.jit_buffer_size=64M, respectively.
This does not affect the default observable behavior,
    as the JIT is still disabled by default.
    However, it is now disabled through the
    opcache.jit setting,
    rather than
    opcache.jit_buffer_size.
    This may affect users who previously enabled JIT through
    opcache.jit_buffer_size
    exclusively, without also specifying a JIT mode using
    opcache.jit.
    To enable JIT compilation, set the
    opcache.jit config value accordingly.
If JIT compilation is enabled, PHP will now exit with a fatal error on
    startup if the initialization of the JIT compiler failed for any reason.
PCNTL
The pcntl_sigprocmask,
   pcntl_sigwaitinfo, and
   pcntl_sigtimedwait functions now always
   return  on failure.
   In some case previously it could return the value -1.
PCRE
The bundled pcre2lib has been updated to version 10.44.
   As a consequence, this means {,3} is now recognized
   as a quantifier instead of as text.
   Furthermore, the meaning of some character classes in UCP mode has changed.
   Consult the PCRE2 Changelog
   for a full changelog.
PDO_DBLIB
The Pdo\Dblib::ATTR_STRINGIFY_UNIQUEIDENTIFIER and
   Pdo\Dblib::ATTR_DATETIME_CONVERT attributes now act as
   boolean attributes instead of integer attributes.
   Thus setting the attribute via PDO::setAttribute
   and retrieving it via PDO::getAttribute expects
   and or return a bool.
PDO_FIREBIRD
The PDO::ATTR_AUTOCOMMIT attribute now act as
   boolean attributes instead of integer attributes.
   Thus setting the attribute via PDO::setAttribute
   and retrieving it via PDO::getAttribute expects
   and or return a bool.
The extension now exposes some Firebird C++ APIs,
   therefore building this extension now requires a C++ compiler.
   Moreover, the extension must now be compiled against fbclient 3.0 or higher.
PDO_MYSQL
The PDO::ATTR_AUTOCOMMIT,
   PDO::ATTR_EMULATE_PREPARES, and
   PDO::MYSQL_ATTR_DIRECT_QUERY attributes now act as
   boolean attributes instead of integer attributes.
   Thus setting the attribute via PDO::setAttribute
   and retrieving it via PDO::getAttribute expects
   and or return a bool.
PDO_PGSQL
The DSN's credentials, when set, are given priority over their PDO
   constructor counterparts, being closer to the documentation states.
SimpleXML
SimpleXMLElement is not only a representation of an
   XML element, but it is also a RecursiveIterator.
   Prior to PHP 8.4.0, some of its methods (e.g.
   SimpleXMLElement::asXML or
   SimpleXMLElement::getName) and casting such
   instances to  would implicitly reset the iterator.
This could cause unexpected infinite loops as the iterator was rewound.
   For example:
   
    

<?php

$xmlString = "<root><a><b>1</b><b>2</b><b>3</b></a></root>";
$xml = simplexml_load_string($xmlString);

$nodes = $xml->a->b;
foreach ($nodes as $nodeData) {
    echo "nodeData: " . $nodeData . "\n";

    $xml = $nodes->asXml();
}


    
    
     would result in an infinite loop.
    
    

nodeData: 1
nodeData: 2
nodeData: 2
nodeData: 2
nodeData: 2
nodeData: 2
nodeData: 2
// ...

    
    
     However, this behavior has now been corrected, and a
     SimpleXMLElement will no longer implicitly reset
     the iterator data, unless explicitly rewound.
     Meaning the previous example would now result in:
    
    

nodeData: 1
nodeData: 2
nodeData: 3
would result in an infinite loop.
However, this behavior has now been corrected, and a
     SimpleXMLElement will no longer implicitly reset
     the iterator data, unless explicitly rewound.
     Meaning the previous example would now result in:
SOAP
SoapClient::$typemap is now an array
   rather than a resource.
   Checks using is_resource (i.e.
   is_resource($client->typemap)) should be
   replaced with checks for  (i.e. $client->typemap !== null).
The SOAP extension gained an optional dependency on the
   session extension.
   If PHP is built without the session extension and with the
   --enable-rtld-now configure flag enabled,
   startup errors will now occur if the SOAP
   extension is also used.
   To solve this either don't use rtld-now or load the session extension.
Standard
When using strcspn with
   characters being the empty string,
   the length of the string is now returned instead of incorrectly stopping
   at the first null byte.
http_build_query now correctly handles backed enums.
stream_bucket_make_writeable and
   stream_bucket_new will now return a
   StreamBucket instance instead of an instance of
   stdClass.
Tidy
Failures in the constructor now throw exceptions rather than emitting
   warnings and having a broken object.
XML
The xml_set_*_handler
   functions now declare and check for an effective
   signature of callablestringnull for the
   handler parameters.
   Moreover, values of type string that correspond to method names,
   of object set with xml_set_object are now checked to
   see if the method exists on the class of the previously passed object.
   This means that xml_set_object must now always be
   called prior to setting method names as callables.
   Passing an empty string to disable the handler is still allowed,
   but deprecated.
However, as xml_set_object and passing
   non-callable strings is deprecated.
   It is recommended to change such instances with a callable
   referring to the method directly.
Other Changes
Core changes
Closures
Closure names have been adjusted to include the parent function's name
    and the line of definition to make them easier to distinguish, for example
    within stack traces.
Fibers
Fiber switching during destructor execution is now allowed. It was previously
    blocked due to conflicts with garbage collection.
Destructors may now be executed in a separate Fiber:
When garbage collection is triggered in a Fiber,
    destructors called by the GC are executed in a separate Fiber:
    the gc_destructor_fiber.
    If this Fiber suspends, a new one is created to execute the remaining
    destructors.
    The previous gc_destructor_fiber is not referenced anymore by the GC
    and may be collected if it's not referenced anywhere else.
    Objects whose destructor is suspended will not be collected until the
    destructor returns or the Fiber is collected.
Output Handlers
Output handler status flags passed to the flags
    parameter of ob_start are now cleared.
output_add_rewrite_var now uses
    url_rewriter.hosts
    instead of
    session.trans_sid_hosts
    for selecting hosts that will be rewritten.
Changes in SAPI Modules
apache2handler
Support for EOL Apache 2.0 and 2.2 has been removed.
    Minimum required Apache version is now 2.4.
CLI
The builtin server looks for an index file recursively by traversing parent
    directories in case the specified file cannot be located.
    This process was previously skipped if the path looked like it was
    referring to a file, i.e. if the last path component contained a period.
    In that case, a 404 error was returned.
    The behavior has been changed to look for an index file in all cases.
FPM
Flushing headers without a body will now succeed.
Status page has a new field to display a memory peak.
The /dev/poll events.mechanism
    setting for Solaris/Illumos had been retired.
Changed Functions
Core
trigger_error and user_error
    now have a return type of true instead of bool.
DOM
DOMDocument::registerNodeClass
    now has a tentative return type of true instead of
    bool.
    It could only ever return  in practice.
Hash
hash_update
    now has a tentative return type of true instead of
    bool.
    It could only ever return  in practice.
Intl
NumberFormatter::ROUND_TOWARD_ZERO and
    NumberFormatter::ROUND_AWAY_FROM_ZERO
    have been added as aliases for
    NumberFormatter::ROUND_DOWN and
    NumberFormatter::ROUND_UP
    to be consistent with the new
    PHP_ROUND_* modes.
ResourceBundle::get
    
    now has a tentative return type of ResourceBundle|array|string|int|null.
The idn_to_ascii and idn_to_utf8
    functions now always throw ValueErrors
    if the domain name is empty or too long.
The idn_to_ascii and idn_to_utf8
    functions now always throw ValueError
    if the variant parameter is not
    INTL_IDNA_VARIANT_UTS46.
LibXML
libxml_set_streams_context now immediately throws a
    TypeError when a non-stream-context
    resource is passed to the function,
    instead of throwing later when the stream context is used.
MBString
The behavior of mb_strcut is more consistent
    now on invalid UTF-8 and UTF-16 strings.
    There is no behavioural change for valid UTF-8 and UTF-16 strings.
ODBC
The row of
    odbc_fetch_object,
    odbc_fetch_array, and
    odbc_fetch_into now have a default value of ,
    consistent with odbc_fetch_row.
    Previously, the default values were
    -1,
    -1,
    and 0,
    respectively.
OpenSSL
The extra_attributes in
    openssl_csr_new sets the CSR
    attributes instead of subject DN, which incorrectly done previously.
The dn in
    openssl_csr_new allows setting an array
    of values for a single entry.
New serial_hex added to
    openssl_csr_sign to allow setting serial numbers
    in the hexadecimal format.
Parsing ASN.1 UTCTime with openssl_x509_parse
    fails if seconds are omitted for OpenSSL version below 3.2
    (-1 is returned for such fields).
    OpenSSL version above 3.3 did not load such certificates already.
PDO
It is now possible to fetch the value of the
    PDO::ATTR_STRINGIFY_FETCHES attribute with
    PDO::getAttribute.
A new PDO::PGSQL_ATTR_RESULT_MEMORY_SIZE
    has been added to retrieve the memory usage of query results with
    PDO::getAttribute for drivers that support it.
PDO_FIREBIRD
It is now possible to fetch the value of the
    
    FB_ATTR_DATE_FORMAT,
    FB_ATTR_TIME_FORMAT,
    FB_ATTR_TIMESTAMP_FORMAT,
    attributes with
    
    PDO::getAttribute.
Added new attributes to specify transaction isolation level and access mode.
    Five constants relating to this functionality have been added:

    
     Pdo\Firebird::TRANSACTION_ISOLATION_LEVEL
     Pdo\Firebird::READ_COMMITTED
     Pdo\Firebird::REPEATABLE_READ
     Pdo\Firebird::SERIALIZABLE
     Pdo\Firebird::WRITABLE_TRANSACTION
When using persistent connections, there is now a liveliness check in the
    constructor.
The content that is built changes depending on the value of
    FB_API_VER in
    ibase.h.
    A new static method Pdo\Firebird::getApiVersion
    can be used to obtain this information.
    This information is also now referenced in phpinfo.
Five new data types are now available:
    
     INT128
     DEC16
     DEC34
     TIMESTAMP_TZ
     TIME_TZ
    
    .
    These are available starting with Firebird 4.0.
PDO_MYSQL
It is now possible to fetch the value of the
    PDO::ATTR_FETCH_TABLE_NAMES attribute with
    
    PDO::getAttribute.
PDO_PGSQL
Support retrieving the memory usage of queries for
    PDO::PGSQL_ATTR_RESULT_MEMORY_SIZE.
If the column is of type FLOAT4OID or
    FLOAT8OID the value will now be returned as a
    float instead of a string.
PGSQL
The conditions parameter of
    pg_select is now optional and accepts an empty array.
Phar
The
    
     Phar::setAlias
     Phar::setDefaultStub
    
    methods now have a tentative return type of true
    instead of bool.
POSIX
posix_isatty now sets the error number when the
    file descriptor/stream argument is invalid.
Reflection
ReflectionGenerator::getFunction
    may now be called after the generator finished executing.
Sockets
The backlog parameter of
    socket_create_listen now has a default value of
    SOMAXCONN.
    Previously, it was 128.
Sodium
The sodium_crypto_aead_aes256gcm_*
    functions are now available on aarch64 CPUs with the ARM cryptographic
    extensions.
SPL
The
    
     SplPriorityQueue::insert
     SplPriorityQueue::recoverFromCorruption
     SplHeap::insert
     SplHeap::recoverFromCorruption
    
    methods now have a tentative return type of true
    instead of bool.
SplObjectStorage now implements
    SeekableIterator.
Standard
The default 'cost' value for the PASSWORD_BCRYPT
    hashing algorithm for password_hash has been increased from
    10 to 12.
debug_zval_dump now indicates whether an array is packed.
long2ip now has a return type of string
    
    instead of string|false.
highlight_string now has a return type of
    string|true instead of string|bool.
print_r now has a return type of
    string|true instead of string|bool.
Rounding with round
The mode parameter of the
     round function has been widened to
     
     RoundingMode|int,
     
     accepting instances of a new RoundingMode enum.
Four new modes have been added to the round function:
     
      RoundingMode::PositiveInfinity
      RoundingMode::NegativeInfinity
      RoundingMode::TowardsZero
      RoundingMode::AwayFromZero
The internal implementation for rounding to integers has been rewritten
     to be easier to verify for correctness and to be easier to maintain.
     Some rounding bugs have been fixed as a result of the rewrite.
     For example previously rounding 0.49999999999999994
     to the nearest integer would have resulted in 1.0
     instead of the correct result 0.0.
     Additional inputs might also be affected and result in different outputs
     compared to earlier PHP versions.
Fixed a bug caused by "pre-rounding" of the round function.
     Previously, using "pre-rounding" to treat a value like 0.285
     (actually 0.28499999999999998) as a decimal number
     and round it to 0.29.
     However, "pre-rounding" incorrectly rounds certain numbers,
     so this fix removes "pre-rounding" and changes the way numbers are compared,
     so that the values are correctly rounded as decimal numbers.
The maximum precision that can be handled by round
     has been extended by one digit.
     For example, round(4503599627370495.5) returned in
     4503599627370495.5,
     but now returns 4503599627370496.
Other Changes to Extensions
cURL
The minimum libcurl version required is now 7.61.0.
The CURLOPT_DNS_USE_GLOBAL_CACHE option no longer
    has any effect, and is silently ignored.
    This underlying feature was deprecated in libcurl 7.11.1,
    and removed in libcurl 7.62.0.
GMP
Casting a GMP object to bool is now
    possible instead of emitting a E_RECOVERABLE_ERROR.
    The casting behaviour is overloaded such that a GMP
    object representing the value 0 is cast to .
LibXML
The minimum libxml2 version required is now 2.9.4.
Intl
The behaviour of Intl class has been normalized to always throw
    Error exceptions when attempting to use
    a non-initialized object, or when cloning fails.
MBString
Unicode data tables have been updated to Unicode 16.0.
MySQLnd
Support for the new VECTOR data type from MySQL 9.
OpenSSL
The minimum OpenSSL version required is now 1.1.1.
PDO_PGSQL
The minimum libpq version required is now 10.0.
PGSQL
The minimum libpq version required is now 10.0.
SPL
Out of bounds accesses in SplFixedArray now throw
    exceptions of type OutOfBoundsException
    instead of RuntimeException.
    Because OutOfBoundsException is a child
    class of RuntimeException no behavioural
    changes are exhibited when attempting to catch those exceptions.
XSL
The typed properties XSLTProcessor::$cloneDocument
    and XSLTProcessor::$doXInclude are now declared.
Zlib
The minimum zlib version required is now 1.2.11.
Performance
Core
Improved the performance of floating point number parsing and formatting in
    ZTS builds under highly concurrent loads.
    This affects the printf family of functions as well
    as serialization functions such as json_encode,
    or serialize.
sprintf using only %s and
    %d specifiers will be compiled into the equivalent
    string interpolation, avoiding the overhead of a function call and
    repeatedly parsing the format string.
BCMath
Improved performance of number conversions and operations.
DOM
The performance of DOMNode::C14N is greatly
    improved for the case without an xpath query.
    This can give a time improvement of easily two order of
    magnitude for documents with tens of thousands of nodes.
Improved performance and reduce memory consumption of XML serialization.
Reduced memory usage of node classes.
FTP
Improved the performance of FTP uploads up to a factor of 10x for large
    uploads.
Hash
Added SSE2 and SHA-NI implementations of SHA-256.
    This improves the performance on supported CPUs by ~1.3x (SSE2),
    and 3x - 5x (SHA-NI).
    Credit to Colin Percival / Tarsnap for this optimization.
MBString
mb_strcut is much faster now for UTF-8
    and UTF-16 strings.
Looking up mbstring encoding names is much faster now.
The performance of converting SJIS-win to Unicode is greatly improved.
MySQLnd
Improved the performance of MySQLnd quoting.
PCRE
Improved the performance of named capture groups.
Random
Improved the performance of Random\Randomizer,
    with a specific focus on the
    Random\Randomizer::getBytes,
    and Random\Randomizer::getBytesFromString methods.
SimpleXML
Improved performance and reduce memory consumption of XML serialization.
Standard
The performance of strspn and
    strcspn is greatly improved.
    They now run in linear time instead of being bounded by quadratic time.
Improved the performance of strpbrk.
get_browser is much faster now,
    up to 1.5x - 2.5x for some test cases.
New Features
PHP Core
Property Hooks
Object properties may now have additional logic associated with their
    get and set operations.
    Depending on the usage, that may or may not make the property virtual,
    that is, it has no backing value at all.
Asymmetric Property Visibility
Object properties may now have their set visibility
    controlled separately from the get visibility.
Lazy Objects
It is now possible to create objects whose initialization is deferred until
    they are accessed. Libraries and frameworks can leverage these lazy objects
    to defer fetching data or dependencies required for initialization.
#[\Deprecated] attribute
The new Deprecated attribute can be used to mark functions, methods,
    and class constants as deprecated. The behavior of functionality deprecated with this
    attribute matches the behavior of the existing deprecation mechanism for functionality
    provided by PHP itself. The only exception is that the emitted error code is
    E_USER_DEPRECATED instead of E_DEPRECATED.
Existing deprecations in functionality provided by PHP itself have been updated to use
    the attribute, improving the emitted error messages by including a short explanation.
Parsing RFC1867 (multipart) requests in non-POST HTTP requests
Added request_parse_body function that allows parsing
    RFC1867 (multipart) requests in non-POST HTTP requests.
Chaining  expressions without parentheses
New expressions with constructor arguments are now dereferencable, meaning
    they allow chaining method calls, property accesses, etc. without enclosing
    the expression in parentheses.
Improved Debugging Info for WeakReference
Getting the debug info for WeakReference will now
    also output the object it references, or  if the reference is no
    longer valid.
Improved Debugging Info for Closure
The output of Closure::__debugInfo now includes
    the name, file, and line of the Closure.
Defining Identical Symbols in Different Namespace Blocks
Exiting a namespace now clears seen symbols.
    This allows using a symbol in a namespace block, even if a previous
    namespace block declared a symbol with the same name.
cURL
curl_version returns an additional
   feature_list value, which is an associative array
   of all known cURL features, and whether they are supported ()
   or not ().
Added CURL_HTTP_VERSION_3 and
   CURL_HTTP_VERSION_3ONLY constants (available
   since libcurl 7.66 and 7.88) as available options for
   CURLOPT_HTTP_VERSION.
Added CURLOPT_PREREQFUNCTION as a cURL option that
   accepts a callable to be called after the connection is made,
   but before the request is sent.
   This callable must return either CURL_PREREQFUNC_OK or
   CURL_PREREQFUNC_ABORT to allow or abort the request.
Added CURLOPT_SERVER_RESPONSE_TIMEOUT,
   which was formerly known as CURLOPT_FTP_RESPONSE_TIMEOUT.
   Both constants hold the same value.
Added CURLOPT_DEBUGFUNCTION as a cURL option that
   accepts a callable that gets called during the request lifetime
   with the CurlHandle object,
   an integer containing the debug message type, and a string containing the
   debug message.
   The debug message type is one of the following constants:
   
    CURLINFO_TEXT
    CURLINFO_HEADER_IN
    CURLINFO_HEADER_OUT
    CURLINFO_DATA_IN
    CURLINFO_DATA_OUT
    CURLINFO_SSL_DATA_IN
    CURLINFO_SSL_DATA_OUT
   
   Once this option is set, CURLINFO_HEADER_OUT
   must not be set because it uses the same libcurl functionality.
The curl_getinfo now returns an additional
   posttransfer_time_us key, containing the number of
   microseconds from the start until the last byte is sent.
   When a redirect is followed, the time from each request is added together.
   This value can also be retrieved by passing
   CURLINFO_POSTTRANSFER_TIME_T to the
   curl_getinfo option parameter.
   This requires libcurl 8.10.0 or later.
DOM
Added the Dom namespace with new classes as counterparts
   to the existing DOM classes (e.g. Dom\Node is the new
   DOMNode).
   These classes are compatible with HTML 5 and are WHATWG spec-compliant;
   solving long-standing bugs in the DOM extension.
   The old DOM classes remain available for backwards compatibility.
Added the DOMNode::compareDocumentPosition
   with its associated constants:
   
    DOMNode::DOCUMENT_POSITION_DISCONNECTED
    DOMNode::DOCUMENT_POSITION_PRECEDING
    DOMNode::DOCUMENT_POSITION_FOLLOWING
    DOMNode::DOCUMENT_POSITION_CONTAINS
    DOMNode::DOCUMENT_POSITION_CONTAINED_BY
    DOMNode::DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC
It is now possible to pass any callable to
   DOMXPath::registerPhpFunctions.

   Furthermore, with DOMXPath::registerPhpFunctionNs,
   callbacks can now be registered that will use native function call syntax
   rather than using php:function('name').
Intl
Added the NumberFormatter::ROUND_HALFODD to
   complement the existing NumberFormatter::ROUND_HALFEVEN
   functionality.
OpenSSL
Added support for Curve25519 + Curve448 based keys.
   Specifically x25519, ed25519, x448 and ed448 fields are supported in
   openssl_pkey_new,
   openssl_pkey_get_details,
   openssl_sign, and
   openssl_verify were extended to support those keys.
Implement PASSWORD_ARGON2 password hashing.
   Requires OpenSSL 3.2 and NTS build.
PCRE
The bundled pcre2lib has been updated to version 10.44.
   As a consequence, LoongArch JIT support has been added, spaces
   are now allowed between braces in Perl-compatible items, and
   variable-length lookbehind assertions are now supported.
With pcre2lib version 10.44, the maximum length of named capture groups
   has changed from 32 to 128.
Added support for the r (PCRE2_EXTRA_CASELESS_RESTRICT)
   modifier, as well as the (?r) mode modifier.
   When enabled along with the case-insensitive modifier (i),
   the expression locks out mixing of ASCII and non-ASCII characters.
PDO
Added support for driver-specific subclasses in order to better support
   database-specific functionalities.
   The new classes are instantiatable either via calling the
   PDO::connect method or by instantiating one
   of the driver-specific subclasses directly.
Added support for driver specific SQL parsers.
   When a driver-specific parser is not available, the default parser is used.
   The default parser supports:
   
    
     single and double-quoted literals, with doubling as escaping mechanism
    
    
     two-dashes and non-nested C-style comments
PDO_MYSQL
Added a custom parser supporting:
   
    
     single and double-quoted literals, with doubling and backslash as escaping
     mechanism
    
    
     backtick literal identifiers and with doubling as escaping mechanism
    
    
     two dashes followed by at least 1 whitespace, non-nested C-style comments,
     and hash-comments
PDO_PGSQL
Added a custom parser supporting:
   
    
     single and double-quoted literals, with doubling as escaping mechanism
    
    
     C-style "escape" string literals (E'string')
    
    
     dollar-quoted string literals
    
    
     two-dashes and C-style comments (non-nested)
    
    
     support for ?? as escape sequence for the
     ? operator
PDO_SQLITE
Added a custom parser supporting:
   
    
     single, double-quoted, and backtick literals, with doubling as
     escaping mechanism
    
    
     square brackets quoting for identifiers
    
    
     two-dashes and C-style comments (non-nested)
Phar
Added support for the Unix timestamp extension for Zip archives.
Readline
Added ability to change the .php_history path through
   the PHP_HISTFILE environment variable.
Reflection
ReflectionAttribute now contains a
   name property to improve the debugging experience.
ReflectionClassConstant::__toString and
   ReflectionProperty::__toString now returns the
   attached doc comments.
Multiple new methods and constants which are related to the lazy objects
   feature have been added:

   
    
     ReflectionClass::newLazyGhost
    
    
     ReflectionClass::newLazyProxy
    
    
     ReflectionClass::resetAsLazyGhost
    
    
     ReflectionClass::resetAsLazyProxy
    
    
     ReflectionClass::isUninitializedLazyObject
    
    
     ReflectionClass::initializeLazyObject
    
    
     ReflectionClass::markLazyObjectAsInitialized
    
    
     ReflectionClass::getLazyInitializer
    
    
     ReflectionProperty::skipLazyInitialization
    
    
     ReflectionProperty::setRawValueWithoutLazyInitialization
    
    
     ReflectionClass::SKIP_INITIALIZATION_ON_SERIALIZE
    
    
     ReflectionClass::SKIP_DESTRUCTOR
SOAP
Added support for clark notation for namespaces in class map.
   It is now possible to specify entries in a class map with clark notation
   to resolve a type with a specific namespace to a specific class.
   For example: '{http://example.com}foo' => 'FooClass'.
Instances of DateTimeInterface that are
   passed to xsd:datetime or similar elements are now
   serialized as such instead of being serialized as an empty string.
Session persistence now works with a shared session module.
Standard
Added a new RoundingMode enum with clearer naming
   and improved discoverability compared to the
   PHP_ROUND_* constants.
   Moreover, four new rounding modes were added which are only available via
   the new RoundingMode enum.
XSL
It is now possible to use parameters that contain both single and double
   quotes.
It is now possible to pass any callable to
   XSLTProcessor::registerPhpFunctions.
Added XSLTProcessor::$maxTemplateDepth and
   XSLTProcessor::$maxTemplateVars
   to control the recursion depth of XSL template evaluation.
Zip
Added the ZipArchive::ER_TRUNCATED_ZIP
   constant, which was added in libzip 1.11.
Deprecated Features
PHP Core
Implicitly nullable parameter
A parameter's type is implicitly widened to accept null
    if the default value for it is .
The following code:
    
     

<?php
function foo(T1 $a = null) {}

     
    
    should be converted to:
    
     

<?php
function foo(T1|null $a = null) {}

     
    
    or
    
     

<?php
function foo(?T1 $a = null) {}
However, if such a parameter declaration is followed by a mandatory
    parameter:
    
     

<?php
function foo(T1 $a, T2 $b = null, T3 $c) {}

     
    
    It must be converted to:
    
     

<?php
function foo(T1 $a, T2|null $b, T3 $c) {}

     
    
    or
    
     

<?php
function foo(T1 $a, ?T2 $b, T3 $c) {}

     
    
    as optional parameter before required ones are deprecated.
Raising zero to the power of negative number
Raising a number to the power of a negative number is equivalent to taking
    the reciprocal of the number raised to the positive opposite of the power.
    That is, 10-2 is the same as
    1 / 102.
    Therefore raising 0 to the power of a negative number
    corresponds to dividing by 0, i.e.
    0-2 is the same as
    1 / 02, or
    1 / 0. Thus, this behavior has been deprecated.
This affects the exponentiation operator **
    and the pow function.
If the IEEE 754 semantics are desired one should use the new
    fpow function.
Using underscore _ as class name
Naming a class _ is now deprecated:
    
     

<?php
class _ {}
Classes whose names start with an underscore are not
     deprecated:
     
      

<?php
class _MyClass {}
Using trigger_error with
    E_USER_ERROR
Calling trigger_error with
    error_level being equal to
    E_USER_ERROR is now deprecated.
Such usages should be replaced by either throwing an exception,
    or calling exit, whichever is more appropriate.
The E_STRICT constant
Because the E_STRICT error level was removed,
    this constant is now deprecated.
cURL
The CURLOPT_BINARYTRANSFER constant is now deprecated.
Date
The  DatePeriod::__construct(string $isostr, int $options = 0)
   signature has been deprecated.
   Use DatePeriod::createFromISO8601String instead.
The SUNFUNCS_RET_TIMESTAMP,
   SUNFUNCS_RET_STRING,
   and SUNFUNCS_RET_DOUBLE constants are now deprecated.
   This follows from the deprecation of the date_sunset and
   date_sunrise functions in PHP 8.1.0.
DBA
Passing  or  to dba_key_split is now
   deprecated.
   It would always return  in those cases.
DOM
The DOM_PHP_ERR constant is now deprecated.
The following properties have been formally deprecated:
   
    DOMDocument::$actualEncoding
    DOMDocument::$config
    DOMEntity::$actualEncoding
    DOMEntity::$encoding
    DOMEntity::$version
Hash
Passing invalid options to hash functions is now deprecated.
Intl
Calling intlcal_set or
   IntlCalendar::set
   with more than two arguments is deprecated.
   Use either IntlCalendar::setDate or
   IntlCalendar::setDateTime instead.
Calling intlgregcal_create_instance or
   IntlGregorianCalendar::__construct
   with more than two arguments is deprecated.
   Use either IntlGregorianCalendar::createFromDate or
   IntlGregorianCalendar::createFromDateTime instead.
LDAP
Calling ldap_connect
   with more than two arguments is deprecated.
   Use ldap_connect_wallet instead.
Calling ldap_exop
   with more than four arguments is deprecated.
   Use ldap_exop_sync instead.
MySQLi
The mysqli_ping function and
   mysqli::ping method
   are now deprecated as the reconnect feature was removed in PHP 8.2.0.
The mysqli_kill function and
   mysqli::kill method
   are now deprecated.
   If this functionality is needed a SQL KILL command
   can be used instead.
The mysqli_refresh function and
   mysqli::refresh method
   are now deprecated.
   If this functionality is needed a SQL FLUSH command
   can be used instead.
   All MYSQLI_REFRESH_*
   constants have been deprecated as well.
Passing the mode parameter to
   mysqli_store_result explicitly has been deprecated.
   As the MYSQLI_STORE_RESULT_COPY_DATA constant was
   only used in conjunction with this function it has also been deprecated.
PDO_PGSQL
Using escaped question marks (??) inside
   dollar-quoted strings is deprecated.
   Because PDO_PGSQL now has its own SQL parser with dollar-quoted strings
   support, it is no longer necessary to escape question marks inside them.
PGSQL
The 2 arguments signature of pg_fetch_result,
   pg_field_prtlen, and
   pg_field_is_null is now deprecated.
   Use the 3 arguments signature with row set to
    instead.
Random
lcg_value is now deprecated,
   as the function is broken in multiple ways.
   Use Random\Randomizer::getFloat instead.
Reflection
Calling ReflectionMethod::__construct
   with one arguments is deprecated.
   Use ReflectionMethod::createFromMethodName instead.
Session
Calling session_set_save_handler
   with more than two arguments is deprecated.
   Use the two arguments signature instead.
Changing the value of the
   session.sid_length and
   session.sid_bits_per_character
   INI settings is deprecated.
   Update the session storage backend to accept 32 character hexadecimal
   session IDs and stop changing these two INI settings instead.
Changing the value of the
   session.use_only_cookies,
   session.use_trans_sid,
   session.trans_sid_tags,
   session.trans_sid_hosts, and
   session.referer_check
   INI settings is deprecated.
   The SID constant is also deprecated.
SOAP
Passing an int to
   SoapServer::addFunction is now deprecated.
   If all PHP functions need to be provided flatten the array returned by
   get_defined_functions.
The SOAP_FUNCTIONS_ALL constant is now deprecated.
SPL
The SplFixedArray::__wakeup method is now
   deprecated, as it implements
   SplFixedArray::__serialize and
   SplFixedArray::__unserialize
   which need to be overwritten instead.
Using the default value for the escape parameter for the
   SplFileObject::setCsvControl,
   SplFileObject::fputcsv, and
   SplFileObject::fgetcsv is now deprecated.
   
   It must be passed explicitly either positionally or via named arguments.
   This does not apply to SplFileObject::fputcsv
   and SplFileObject::fgetcsv if
   SplFileObject::setCsvControl was used to set a
   new default value.
Standard
Calling stream_context_set_option
   with two arguments is deprecated.
   Use stream_context_set_options instead.
Unserializing strings using the uppercase S tag
   with unserialize is deprecated.
Using the default value for the escape parameter for the
   fputcsv,
   fgetcsv, and
   str_getcsv  is now deprecated.
   
   It must be passed explicitly either positionally or via named arguments.
XML
The xml_set_object function has been deprecated.
Passing non-callable strings to the
   xml_set_*
   functions is now deprecated.
New functions
Closure
Closure::call
CSPRNG
random_bytes
random_int
Error Handling and Logging
error_clear_last
Generator
Generator::getReturn
GNU Multiple Precision
gmp_random_seed
Math
intdiv
PCRE
preg_replace_callback_array
PHP Options/Info
gc_mem_caches
get_resources
POSIX
posix_setrlimit
Reflection
ReflectionParameter::getType
ReflectionParameter::hasType
ReflectionFunctionAbstract::getReturnType
ReflectionFunctionAbstract::hasReturnType
Zip
ZipArchive::setCompressionIndex
ZipArchive::setCompressionName
Zlib Compression
inflate_add
deflate_add
inflate_init
deflate_init
Removed Extensions and SAPIs
Removed Extensions
ereg
mssql
mysql
sybase_ct
Removed SAPIs
aolserver
apache
apache_hooks
apache2filter
caudium
continuity
isapi
milter
nsapi
phttpd
pi3web
roxen
thttpd
tux
webjames
New Classes and Interfaces
Intl
IntlChar
Reflection
ReflectionGenerator
ReflectionType
Session Handling
SessionUpdateTimestampHandlerInterface
Exception Hierarchy
Throwable
Error
TypeError
ParseError
AssertionError
ArithmeticError
DivisionByZeroError
Changes in SAPI Modules
FPM
Unqualified listen ports now listen on both
    IPv4 and IPv6
In PHP 5, a listen directive with only a
    port number would listen on all interfaces, but only on IPv4. PHP 7 will
    now accept requests made via both IPv4 and IPv6.
This does not affect directives which include specific IP addresses; these
    will continue to only listen on that address and protocol.
New Global Constants
Core Predefined Constants
PHP_INT_MIN
GD
IMG_WEBP (as of PHP 7.0.10)
JSON
JSON_ERROR_INVALID_PROPERTY_NAME
JSON_ERROR_UTF16
LibXML
LIBXML_BIGLINES
PCRE
PREG_JIT_STACKLIMIT_ERROR
POSIX
POSIX_RLIMIT_AS
POSIX_RLIMIT_CORE
POSIX_RLIMIT_CPU
POSIX_RLIMIT_DATA
POSIX_RLIMIT_FSIZE
POSIX_RLIMIT_LOCKS
POSIX_RLIMIT_MEMLOCK
POSIX_RLIMIT_MSGQUEUE
POSIX_RLIMIT_NICE
POSIX_RLIMIT_NOFILE
POSIX_RLIMIT_NPROC
POSIX_RLIMIT_RSS
POSIX_RLIMIT_RTPRIO
POSIX_RLIMIT_RTTIME
POSIX_RLIMIT_SIGPENDING
POSIX_RLIMIT_STACK
POSIX_RLIMIT_INFINITY
Zlib
ZLIB_ENCODING_RAW
ZLIB_ENCODING_DEFLATE
ZLIB_ENCODING_GZIP
ZLIB_FILTERED
ZLIB_HUFFMAN_ONLY
ZLIB_FIXED
ZLIB_RLE
ZLIB_DEFAULT_STRATEGY
ZLIB_BLOCK
ZLIB_FINISH
ZLIB_FULL_FLUSH
ZLIB_NO_FLUSH
ZLIB_PARTIAL_FLUSH
ZLIB_SYNC_FLUSH
Backward incompatible changes
Other Changes
Loosening Reserved Word Restrictions
Globally reserved words as property, constant, and method names within classes,
   interfaces, and traits are now allowed. This reduces the surface of BC breaks
   when new keywords are introduced and avoids naming restrictions on APIs.
This is particularly useful when creating internal DSLs with fluent interfaces:
The only limitation is that the class keyword still
   cannot be used as a constant name, otherwise it would conflict with the
   class name resolution syntax (ClassName::class).
Removal of date.timezone Warning
Previously, a warning was emitted if the
   date.timezone INI setting had not
   been set prior to using any date- or time-based functions. Now, this warning
   has been removed (with
   date.timezone still defaulting to
   UTC).
New features
Scalar type declarations
Scalar
   type declarations
   come in two flavours: coercive (default) and strict. The following types
   for parameters can now be enforced (either coercively or strictly): strings
    (string), integers (int), floating-point
    numbers (float), and booleans (bool). They
    augment the other types introduced in PHP 5: class names, interfaces,
    array and callable.
To enable strict mode, a single  directive must be placed at the
   top of the file. This means that the strictness of typing for scalars is
   configured on a per-file basis. This directive not only affects the type
   declarations of parameters, but also a function's return type (see
   return type declarations,
   built-in PHP functions, and functions from loaded
   extensions.
Full documentation and examples of scalar type declarations can be found in
   the
   type declaration
   reference.
Return type declarations
PHP 7 adds support for 
   return type declarations.
   Similarly to
   argument type declarations,
   return type declarations specify the type of the value that will be
   returned from a function. The same
   types
   are available for return type declarations as are available for argument
   type declarations.
Full documentation and examples of return type declarations can be found in
   the
   return type declarations.
   reference.
Null coalescing operator
The null coalescing operator (??) has been added as
   syntactic sugar for the common case of needing to use a ternary in
   conjunction with isset. It returns its first operand
   if it exists and is not ; otherwise it returns its second operand.
Spaceship operator
The spaceship operator is used for comparing two expressions. It returns -1, 0 
   or 1 when $a is respectively less than, equal to, or greater 
   than $b. Comparisons are performed according to PHP's usual
   type comparison rules.
Constant arrays using define
Array constants can now be defined with
   define. In PHP 5.6, they could only be defined with
   .
Anonymous classes
Support for anonymous classes has been added via new
   class. These can be used in place of full class definitions for
   throwaway objects:
Full documentation can be found in the 
   anonymous class reference.
Unicode codepoint escape syntax
This takes a Unicode codepoint in hexadecimal form, and outputs that
   codepoint in UTF-8 to a double-quoted string or a heredoc. Any valid
   codepoint is accepted, with leading 0's being optional.
Closure::call
Closure::call is a more performant, shorthand way
   of temporarily binding an object scope to a closure and invoking it.
Filtered unserialize
This feature seeks to provide better security when unserializing objects on
   untrusted data. It prevents possible code injections by enabling the
   developer to whitelist classes that can be unserialized.
IntlChar
The new IntlChar class seeks to expose additional
   ICU functionality. The class itself defines a number of static methods and
   constants that can be used to manipulate unicode characters.
In order to use this class, the Intl extension must be installed.
Expectations
Expectations are a
   backwards compatible enhancement to the older assert
   function. They allow for zero-cost assertions in production code, and
   provide the ability to throw custom exceptions when the assertion fails.
While the old API continues to be maintained for compatibility,
   assert is now a language construct, allowing the first
   parameter to be an expression rather than just a string to be
   evaluated or a bool value to be tested.
Full details on this feature, including how to configure it in both
   development and production environments, can be found on the manual page
   of the assert language construct.
Group use declarations
Classes, functions and constants being imported from the same 
   can now be grouped together in a single  statement.
Generator Return Expressions
This feature builds upon the generator functionality introduced into PHP 5.5.
   It enables for a return statement to be used within a
   generator to enable for a final expression to be returned (return by
   reference is not allowed). This value can be fetched using the new 
   Generator::getReturn() method, which may only be used
   once the generator has finished yielding values.
Being able to explicitly return a final value from a generator is a handy
   ability to have. This is because it enables for a final value to be returned
   by a generator (from perhaps some form of coroutine computation) that can be
   specifically handled by the client code executing the generator. This is far
   simpler than forcing the client code to firstly check whether the final
   value has been yielded, and then if so, to handle that value specifically.
Generator delegation
Generators can now delegate to another generator,
   Traversable object or array
   automatically, without needing to write boilerplate in the outermost
   generator by using the  construct.
Integer division with intdiv
The new intdiv function performs an integer division
   of its operands and returns it.
Session options
session_start now accepts an array of
   options that override the
   session configuration directives
   normally set in php.ini.
These options have also been expanded to support
   session.lazy_write, which is
   on by default and causes PHP to only overwrite any session file if the
   session data has changed, and read_and_close, which is
   an option that can only be passed to session_start to
   indicate that the session data should be read and then the session should
   immediately be closed unchanged.
For example, to set
   session.cache_limiter to
   private and immediately close the session after reading
   it:
preg_replace_callback_array
The new preg_replace_callback_array function enables
   code to be written more cleanly when using the
   preg_replace_callback function. Prior to PHP 7,
   callbacks that needed to be executed per regular expression required the
   callback function to be polluted with lots of branching.
Now, callbacks can be registered to each regular expression using an
   associative array, where the key is a regular expression and the value is a
   callback.
CSPRNG Functions
Two new functions have been added to generate cryptographically secure
   integers and strings in a cross platform way:
   random_bytes and random_int.
list can always unpack objects implementing
   ArrayAccess
Previously, list was not guaranteed to operate
   correctly with objects implementing ArrayAccess.
   This has been fixed.
Other Features
Class member access on cloning has been added,
     e.g. (clone $foo)-bar().
Changed functions
PHP Core
debug_zval_dump now prints "int" instead of "long",
     and "float" instead of "double"
dirname now optionally takes a second parameter,
     depth, to get the name of the directory
     depth levels up from the current directory.
getrusage is now supported on Windows.
mktime and gmmktime functions
     no longer accept is_dst parameter.
preg_replace function no longer supports
     "\e" (PREG_REPLACE_EVAL). preg_replace_callback
     should be used instead.
setlocale function no longer accepts category
     passed as string. LC_* constants must be used instead.
exec, system and passthru
     functions have NULL byte protection now.
shmop_open now returns a resource instead of an int,
     which has to be passed to shmop_size,
     shmop_write, shmop_read,
     shmop_close and shmop_delete.
substr and iconv_substr now return an empty string,
     if string is equal to start characters long.
xml_parser_free is no longer sufficient to free the
     parser resource, if it references an object and this object references that
     parser resource. In this case it is necessary to additionally unset the $parser.
Deprecated features in PHP 7.0.x
PHP 4 style constructors
PHP 4 style constructors (methods that have the same name as the class they
   are defined in) are deprecated, and will be removed in the future. PHP 7
   will emit E_DEPRECATED if a PHP 4 constructor is the
   only constructor defined within a class. Classes that implement a
   __construct method are unaffected.
Static calls to non-static methods
Static calls to methods that
   are not declared static are deprecated, and may be
   removed in the future.
password_hash salt option
The salt option for the password_hash function has been
   deprecated to prevent developers from generating their own (usually insecure)
   salts. The function itself generates a cryptographically secure salt when no
   salt is provided by the developer - therefore custom salt generation should not
   be needed.
capture_session_meta SSL context option
The capture_session_meta SSL context option has been
   deprecated. SSL metadata is now available through the
   stream_get_meta_data function.
LDAP deprecations
The following function has been deprecated:
ldap_sort
Other backward incompatible changes
New objects cannot be assigned by reference
The result of the  statement can no longer be assigned to a variable
   by reference:
Invalid class, interface and trait names
The following names cannot be used to name classes, interfaces or traits:
bool
int
float
string
Furthermore, the following names should not be used. Although they will not
   generate an error in PHP 7.0, they are reserved for future use and should
   be considered deprecated.
resource
object
mixed
numeric
ASP and script PHP tags removed
Support for using ASP and script tags to delimit PHP code has been removed.
   The affected tags are:
Removed ASP and script tags
Calls from incompatible context removed
Previously deprecated in PHP 5.6,
   static calls made to a non-static method with an incompatible context will
   now result in the called method having an undefined
   $this variable and a deprecation warning being issued.
is now a right associative operator
The  construct no longer requires parentheses, and has been changed
   to a right associative operator with precedence between
   print and =. This can result in
   changed behaviour:
Parentheses can be used to disambiguate those cases.
Functions cannot have multiple parameters with the same name
It is no longer possible to define two or more function parameters with the
   same name. For example, the following function will trigger an
   E_COMPILE_ERROR:
Functions inspecting arguments report the current parameter value
func_get_arg, func_get_args,
   debug_backtrace and exception backtraces will no longer
   report the original value that was passed to a parameter, but will instead
   provide the current value (which might have been modified).
Switch statements cannot have multiple default blocks
It is no longer possible to define two or more default blocks in a switch
   statement. For example, the following switch statement will trigger an
   E_COMPILE_ERROR:
$HTTP_RAW_POST_DATA removed
$HTTP_RAW_POST_DATA is no longer available. The
   php://input
   stream should be used instead.
# comments in INI files removed
Support for prefixing comments with # in INI files has been
   removed. ; (semi-colon) should be used instead. This change
   applies to , as well as files handled by
   parse_ini_file and parse_ini_string.
JSON extension replaced with JSOND
The JSON extension has been replaced with JSOND, causing three minor BC
   breaks. Firstly, a number must not end in a decimal point (i.e.
   34. must be changed to either 34.0 or
   34). Secondly, when using scientific notation, the
   e exponent must not immediately follow a decimal point
   (i.e. 3.e3 must be changed to either
   3.0e3 or 3e3).
   Finally, an empty string is no longer considered valid JSON.
Internal function failure on overflow
Previously, internal functions would silently truncate numbers produced from
   float-to-integer coercions when the float was too large to represent as an
   integer. Now, an E_WARNING will be emitted and  will be returned.
Fixes to custom session handler return values
Any predicate functions implemented by custom session handlers that return
   either  or -1 will be fatal errors. If any value
   from these functions other than a boolean, -1, or
   0 is returned, then it will fail and an E_WARNING will be
   emitted.
Sort order of equal elements
The internal sorting algorithm has been improved, what may result in
   different sort order of elements, which compare as equal, than before.
Don't rely on the order of elements which compare as equal; it might change
    anytime.
Misplaced break and continue statements
break and continue statements outside of
   a loop or switch control structure are now detected at
   compile-time instead of run-time as before, and trigger an
   E_COMPILE_ERROR.
Constant disallowed as break and continue argument
break and continue statements no longer
   allow their argument to be a constant, and trigger a
   E_COMPILE_ERROR.
Mhash is not an extension anymore
The Mhash extension has been fully integrated into the Hash extension. Therefore, it is no longer
   possible to detect Mhash support with extension_loaded;
   use function_exists instead. Furthermore, Mhash is no
   longer reported by get_loaded_extensions and related
   features.
declare(ticks)
The declare(ticks)
   directive does no longer leak into different compilation units.
Changes to string handling
Hexadecimal strings are no longer considered numeric
Strings containing hexadecimal numbers are no longer considered to be
   numeric. For example:
filter_var can be used to check if a
   string contains a hexadecimal number, and also to convert a
   string of that type to an int:
\u{ may cause errors
Due to the addition of the new
   Unicode codepoint escape syntax,
   strings containing a literal \u{ followed by an invalid
   sequence will cause a fatal error. To avoid this, the leading backslash
   should be escaped.
Changes to
Minor changes have been made to the behaviour of the  control
  structure, primarily around the handling of the internal array pointer and
  modification of the array being iterated over.
no longer changes the internal array pointer
Prior to PHP 7, the internal array pointer was modified while an array was
   being iterated over with . This is no longer the case, as shown
   in the following example:
by-value operates on a copy of the array
When used in the default by-value mode,  will now operate on a
   copy of the array being iterated rather than the array itself. This means
   that changes to the array made during iteration will not affect the values
   that are iterated.
by-reference has improved iteration behaviour
When iterating by-reference,  will now do a better job of
   tracking changes to the array made during iteration. For example,
   appending to an array while iterating will now result in the appended
   values being iterated over as well:
Iteration of non-Traversable objects
Iterating over a non-Traversable object will now
   have the same behaviour as iterating over by-reference arrays. This
   results in the
   improved behaviour when modifying an array during iteration
   also being applied when properties are added to or removed from the
   object.
Changes to variable handling
PHP 7 now uses an abstract syntax tree when parsing source files. This has
  permitted many improvements to the language which were previously
  impossible due to limitations in the parser used in earlier versions of
  PHP, but has resulted in the removal of a few special cases for consistency
  reasons, which has resulted in backward compatibility breaks. These cases
  are detailed in this section.
Changes to the handling of indirect variables, properties, and methods
Indirect access to variables, properties, and methods will now be
   evaluated strictly in left-to-right order, as opposed to the previous mix
   of special cases. The table below shows how the order of evaluation has
   changed.
Old and new evaluation of indirect expressions
    
     
      
       Expression
       PHP 5 interpretation
       PHP 7 interpretation
      
     
     
      
       
        $$foo['bar']['baz']
       
       
        ${$foo['bar']['baz']}
       
       
        ($$foo)['bar']['baz']
       
      
      
       
        $foo->$bar['baz']
       
       
        $foo->{$bar['baz']}
       
       
        ($foo->$bar)['baz']
       
      
      
       
        $foo->$bar['baz']()
       
       
        $foo->{$bar['baz']}()
       
       
        ($foo->$bar)['baz']()
       
      
      
       
        Foo::$bar['baz']()
       
       
        Foo::{$bar['baz']}()
       
       
        (Foo::$bar)['baz']()
Old and new evaluation of indirect expressions
Code that used the old right-to-left evaluation order must be rewritten to
   explicitly use that evaluation order with curly braces (see the above
   middle column). This will make the code both forwards compatible with PHP
   7.x and backwards compatible with PHP 5.x.
This also affects the  keyword. The curly brace syntax can be
   used to emulate the previous behaviour if required:
Changes to list handling
list no longer assigns variables in reverse order
list will now assign values to variables in the
    order they are defined, rather than reverse order. In general, this only
    affects the case where list is being used in
    conjunction with the array [] operator, as shown below:
In general, it is recommended not to rely on the order in which
    list assignments occur, as this is an implementation
    detail that may change again in the future.
Empty list assignments have been removed
list constructs can no longer be empty. The following
    are no longer allowed:
list cannot unpack strings
list can no longer unpack string
    variables. str_split should be used instead.
Array ordering when elements are automatically created during by reference
   assignments has changed
The order of the elements in an array has changed when those elements have
   been automatically created by referencing them in a by reference
   assignment. For example:
Parentheses around function arguments no longer affect behaviour
In PHP 5, using redundant parentheses around a function argument could
   quiet strict standards warnings when the function argument was passed by
   reference. The warning will now always be issued.
Removed functions
call_user_method and
   call_user_method_array
These functions were deprecated in PHP 4.1.0 in favour of
   call_user_func and
   call_user_func_array. You may also want to consider
   using
   variable functions
   and/or the
   ...
   operator.
All ereg* functions
All ereg functions were removed.
   PCRE is a recommended alternative.
mcrypt aliases
The deprecated mcrypt_generic_end function has been
   removed in favour of mcrypt_generic_deinit.
Additionally, the deprecated mcrypt_ecb,
   mcrypt_cbc, mcrypt_cfb and
   mcrypt_ofb functions have been removed in favour of
   using mcrypt_decrypt with the appropriate
   MCRYPT_MODE_* constant.
All ext/mysql functions
All ext/mysql functions were removed. For
   details about choosing a different MySQL API, see
   Choosing a MySQL API.
All ext/mssql functions
All ext/mssql functions were removed.
   
    PDO_SQLSRV
    PDO_ODBC
    SQLSRV
    Unified ODBC API
intl aliases
The deprecated datefmt_set_timezone_id and
   IntlDateFormatter::setTimeZoneID aliases have been
   removed in favour of datefmt_set_timezone and
   IntlDateFormatter::setTimeZone, respectively.
set_magic_quotes_runtime
set_magic_quotes_runtime, along with its alias
   magic_quotes_runtime, have been removed. They were
   deprecated in PHP 5.3.0, and became effectively non-functional with the
   removal of magic quotes in PHP 5.4.0.
set_socket_blocking
The deprecated set_socket_blocking alias has been
   removed in favour of stream_set_blocking.
dl in PHP-FPM
dl can no longer be used in PHP-FPM. It remains
   functional in the CLI and embed SAPIs.
GD Type1 functions
Support for PostScript Type1 fonts has been removed from the GD extension,
   resulting in the removal of the following functions:
imagepsbbox
imagepsencodefont
imagepsextendfont
imagepsfreefont
imagepsloadfont
imagepsslantfont
imagepstext
Using TrueType fonts and their associated functions is recommended instead.
Changes to error and exception handling
Many fatal and recoverable fatal errors have been converted to exceptions in
  PHP 7. These error exceptions inherit from the Error
  class, which itself implements the Throwable
  interface (the new base interface all exceptions inherit).
This means that custom error handlers may no longer be triggered because
  exceptions may be thrown instead (causing new fatal errors for uncaught
  Error exceptions).
A fuller description of how errors operate in PHP 7 can be found
  on the PHP 7 errors page. This
  migration guide will merely enumerate the changes that affect backward
  compatibility.
set_exception_handler is no longer guaranteed to
   receive Exception objects
Code that implements an exception handler registered with
   set_exception_handler using a type declaration of
   Exception will cause a fatal error when an
   Error object is thrown.
If the handler needs to work on both PHP 5 and 7, you should remove the
   type declaration from the handler, while code that is being migrated to
   work on PHP 7 exclusively can simply replace the
   Exception type declaration with
   Throwable instead.
Internal constructors always throw exceptions on failure
Previously, some internal classes would return  or an unusable object
   when the constructor failed. All internal classes will now throw an
   Exception in this case in the same way that user
   classes already had to.
Parse errors throw ParseError
Parser errors now throw a ParseError object. Error
   handling for eval should now include a  block
   that can handle this error.
E_STRICT notices severity changes
All of the E_STRICT notices have been reclassified to
   other levels. E_STRICT constant is retained, so calls like
   error_reporting(E_ALL|E_STRICT) will not cause an error.
E_STRICT notices severity changes
     
      
       
        Situation
        New level/behaviour
       
      
      
       
        Indexing by a resource
        E_NOTICE
       
       
        Abstract static methods
        Notice removed, triggers no error
       
       
        "Redefining" a constructor
        Notice removed, triggers no error
       
       
        Signature mismatch during inheritance
        E_WARNING
       
       
        Same (compatible) property in two used traits
        Notice removed, triggers no error
       
       
        Accessing static property non-statically
        E_NOTICE
       
       
        Only variables should be assigned by reference
        E_NOTICE
       
       
        Only variables should be passed by reference
        E_NOTICE
       
       
        Calling non-static methods statically
        E_DEPRECATED
E_STRICT notices severity changes
Changes to int handling
Invalid octal literals
Previously, octal literals that contained invalid numbers were silently
   truncated (0128 was taken as 012).
   Now, an invalid octal literal will cause a parse error.
Negative bitshifts
Bitwise shifts by negative numbers will now throw an
   ArithmeticError:
Out of range bitshifts
Bitwise shifts (in either direction) beyond the bit width of an
   int will always result in 0. Previously, the behaviour of
   such shifts was architecture dependent.
Changes to Division By Zero
Previously, when 0 was used as the divisor for either the divide (/) or
   modulus (%) operators, an E_WARNING would be emitted and
   false would be returned. Now, the divide operator
   returns a float as either +INF, -INF, or NAN, as specified by IEEE 754. The modulus operator E_WARNING
   has been removed and will throw a DivisionByZeroError
   exception.
Removed INI directives
Removed features
The following INI directives have been removed as their associated features
   have also been removed:
always_populate_raw_post_data
asp_tags
xsl.security_prefs
The xsl.security_prefs directive has been removed.
   Instead, the XsltProcessor::setSecurityPrefs
   method should be called to control the security preferences on a
   per-processor basis.
None besides functions from the standard C library which are
   always available.
Factorial function using GMP
   

<?php
function fact($x) 
{
    $return = 1;
    for ($i=2; $i <= $x; $i++) {
        $return = gmp_mul($return, $i);
    }
    return $return;
}

echo gmp_strval(fact(1000)) . "\n";
?>
Factorial function using GMP
This will calculate factorial of 1000 (pretty big number)
  very fast.
As of PHP 8.1.0, crypt can be built against a system crypt library
   by specifying the --with-external-libcrypt configure option.
For Argon2 password hashing, either
   libargon2 is required or, as of
   PHP 8.4.0, OpenSSL version 3.2 or later. As of PHP 7.3.0, libargon2 version
   20161029 or later is required if libargon2 is used.
However, to enable Argon2 password hashing, PHP must be built either with
   libargon2 support using the
   --with-password-argon2 configure option
   or, starting from PHP 8.4.0, with OpenSSL using
   --with-openssl and
   --with-openssl-argon2.
Prior to PHP 8.1.0, it was possible to specify the argon2 directory with
   --with-password-argon2[=DIR].
Get error message from last internationalization function called.
Description of an error occurred in the last API function call.
intl_get_error_message example
    

<?php
if( Collator::getAvailableLocales() === false ) {
    show_error( intl_get_error_message() );
}
?>
intl_get_error_message example
intl_error_name
    intl_get_error_code
    intl_is_failure
    collator_get_error_message
    numfmt_get_error_message
errorCode
     
      
       is a value that returned by functions:
       intl_get_error_code,
       collator_get_error_code .
is a value that returned by functions:
       intl_get_error_code,
       collator_get_error_code .
if it the code indicates some failure, and 
   in case of success or a warning.
intl_is_failure example
    

<?php
function check( $err_code )
{
    var_export( intl_is_failure( $err_code ) );
    echo "\n";
}

check( U_ZERO_ERROR );
check( U_USING_FALLBACK_WARNING );
check( U_ILLEGAL_ARGUMENT_ERROR );
?>

    
    
    

false
false
true
intl_is_failure example
intl_get_error_code
    collator_get_error_code
    Collator-getErrorCode
Useful to handle errors occurred in static methods when there's no object to
   get error code from.
Error code returned by the last API function call.
intl_get_error_code example
    

<?php
$coll = collator_create( '<bad_param>' );
if( !$coll ) {
    handle_error( intl_get_error_code() );
}
?>
intl_get_error_code example
intl_is_failure
    intl_error_name
    intl_get_error_message
    collator_get_error_code
    numfmt_get_error_code
Return ICU error code name.
errorCode
     
      
       ICU error code.
ICU error code.
The returned string will be the same as the name of the error code
   constant.
intl_error_name example
    

<?php
$coll     = collator_create( 'en_RU' );
$err_code = collator_get_error_code( $coll );

printf( "Symbolic name for %d is %s\n.", $err_code, intl_error_name( $err_code ) );
?>

    
    
    

Symbolic name for -128 is U_USING_FALLBACK_WARNING.
intl_error_name example
intl_is_failure
    intl_get_error_code
    intl_get_error_message
MySQL Drivers and Plugins
PHP offers several MySQL drivers and plugins for accessing and
    handling MySQL.
The differences and functionality of the MySQL extensions are described
    within the overview of this section.
The extensions listed support the MySQL protocol.
    Examples of compatible database servers are
    MariaDB Server,
    MySQL Server,
    Percona Server for MySQL,
    and
    TiDB.
Overview of the MySQL PHP drivers
Introduction
There are several PHP APIs
    for accessing the MySQL database. Users can choose between the
    mysqli or
    PDO_MySQL extensions.
This guide explains the
    terminology used to describe
    each API, information about
    choosing which API to
    use, and also information to help choose which MySQL
    library to use with
    the API.
Here is a simple example PHP script using the tokenizer that 
  will read in a PHP file, strip all comments from the source
  and print the pure code only.
Strip comments with the tokenizer
Stream Errors
As with any file or socket related function, an operation on a stream
  may fail for a variety of normal reasons (i.e.: Unable to connect to remote
  host, file not found, etc...).  A stream related call may also fail because
  the desired stream is not registered on the running system.  See the array returned
  by stream_get_wrappers for a list of streams supported by your
  installation of PHP.  As with most PHP internal functions
  if a failure occurs an E_WARNING message will be generated
  describing the nature of the error.
Stream Filters
A filter is a final piece of code which may perform
  operations on data as it is being read from or written to a stream.
  Any number of filters may be stacked onto a stream. Custom
  filters can be defined in a PHP script using
  stream_filter_register or in an extension.
  To access the list of currently 
  registered filters, use stream_get_filters.
Using file_get_contents
    to retrieve data from multiple sources
   

<?php
/* Read local file from /home/bar */
$localfile = file_get_contents("/home/bar/foo.txt");

/* Identical to above, explicitly naming FILE scheme */
$localfile = file_get_contents("file:///home/bar/foo.txt");

/* Read remote file from www.example.com using HTTP */
$httpfile  = file_get_contents("http://www.example.com/foo.txt");

/* Read remote file from www.example.com using HTTPS */
$httpsfile = file_get_contents("https://www.example.com/foo.txt");

/* Read remote file from ftp.example.com using FTP */
$ftpfile   = file_get_contents("ftp://user:pass@ftp.example.com/foo.txt");

/* Read remote file from ftp.example.com using FTPS */
$ftpsfile  = file_get_contents("ftps://user:pass@ftp.example.com/foo.txt");
?>
Using file_get_contents
    to retrieve data from multiple sources
Making a POST request to an https server
   

<?php
/* Send POST request to https://secure.example.com/form_action.php
* Include form elements named "foo" and "bar" with dummy values
*/

$sock = fsockopen("ssl://secure.example.com", 443, $errno, $errstr, 30);
if (!$sock) die("$errstr ($errno)\n");

$data = "foo=" . urlencode("Value for Foo") . "&bar=" . urlencode("Value for Bar");

fwrite($sock, "POST /form_action.php HTTP/1.0\r\n");
fwrite($sock, "Host: secure.example.com\r\n");
fwrite($sock, "Content-type: application/x-www-form-urlencoded\r\n");
fwrite($sock, "Content-length: " . strlen($data) . "\r\n");
fwrite($sock, "Accept: */*\r\n");
fwrite($sock, "\r\n");
fwrite($sock, $data);

$headers = "";
while ($str = trim(fgets($sock, 4096)))
$headers .= "$str\n";

echo "\n";

$body = "";
while (!feof($sock))
$body .= fgets($sock, 4096);

fclose($sock);
?>
Making a POST request to an https server
Writing data to a compressed file
   

<?php
/* Create a compressed file containing an arbitrary string
* File can be read back using compress.zlib stream or just
* decompressed from the command line using 'gzip -d foo-bar.txt.gz'
*/
$fp = fopen("compress.zlib://foo-bar.txt.gz", "wb");
if (!$fp) die("Unable to create file.");

fwrite($fp, "This is a test.\n");

fclose($fp);
?>
Writing data to a compressed file
Example class registered as stream wrapper
The example below implements a var:// protocol handler that allows
   read/write access to a named global variable using standard filesystem
   stream functions such as fread. The var:// protocol
   implemented below, given the URL "var://foo" will read/write data
   to/from $GLOBALS["foo"].
A Stream for reading/writing global variables
    

<?php

class VariableStream {
    var $position;
    var $varname;

    function stream_open($path, $mode, $options, &$opened_path)
    {
        $url = parse_url($path);
        $this->varname = $url["host"];
        $this->position = 0;

        return true;
    }

    function stream_read($count)
    {
        $ret = substr($GLOBALS[$this->varname], $this->position, $count);
        $this->position += strlen($ret);
        return $ret;
    }

    function stream_write($data)
    {
        $left = substr($GLOBALS[$this->varname], 0, $this->position);
        $right = substr($GLOBALS[$this->varname], $this->position + strlen($data));
        $GLOBALS[$this->varname] = $left . $data . $right;
        $this->position += strlen($data);
        return strlen($data);
    }

    function stream_tell()
    {
        return $this->position;
    }

    function stream_eof()
    {
        return $this->position >= strlen($GLOBALS[$this->varname]);
    }

    function stream_seek($offset, $whence)
    {
        switch ($whence) {
            case SEEK_SET:
                if ($offset < strlen($GLOBALS[$this->varname]) && $offset >= 0) {
                     $this->position = $offset;
                     return true;
                } else {
                     return false;
                }
                break;

            case SEEK_CUR:
                if ($offset >= 0) {
                     $this->position += $offset;
                     return true;
                } else {
                     return false;
                }
                break;

            case SEEK_END:
                if (strlen($GLOBALS[$this->varname]) + $offset >= 0) {
                     $this->position = strlen($GLOBALS[$this->varname]) + $offset;
                     return true;
                } else {
                     return false;
                }
                break;

            default:
                return false;
        }
    }

    function stream_metadata($path, $option, $var) 
    {
        if($option == STREAM_META_TOUCH) {
            $url = parse_url($path);
            $varname = $url["host"];
            if(!isset($GLOBALS[$varname])) {
                $GLOBALS[$varname] = '';
            }
            return true;
        }
        return false;
    }
}

stream_wrapper_register("var", "VariableStream")
    or die("Failed to register protocol");

$myvar = "";

$fp = fopen("var://myvar", "r+");

fwrite($fp, "line1\n");
fwrite($fp, "line2\n");
fwrite($fp, "line3\n");

rewind($fp);
while (!feof($fp)) {
    echo fgets($fp);
}
fclose($fp);
var_dump($myvar);

?>

    
    
    

line1
line2
line3
string(18) "line1
line2
line3
"
A Stream for reading/writing global variables
Observability
Information on installing and configuring FPM can be found in the
  installation and configuration section of
  the PHP manual.
This function returns a unique identifier for the current thread.
Returns the thread id as an integer.
zend_thread_id example
    

<?php
$thread_id = zend_thread_id();

echo 'Current thread id is: ' . $thread_id;
?>

    
    
    

Current thread id is: 7864
zend_thread_id example
This function is only available if PHP has been built with ZTS (Zend
    Thread Safety) support and debug mode (--enable-debug).
curl_setopt
Enables the use of an abstract Unix domain socket instead of
     establishing a TCP connection to a host and sets the path to
     the given string. This option shares the same semantics
     as CURLOPT_UNIX_SOCKET_PATH. These two options
     share the same storage and therefore only one of them can be set
     per handle.
     Available as of PHP 7.3.0 and cURL 7.53.0.
Sets a string with the contents
     of the Accept-Encoding: header sent in an HTTP request.
     Set to  to disable sending the Accept-Encoding: header.
     Defaults to .
     Available as of cURL 7.21.6.
The maximum number of milliseconds to wait for a server
     to connect back to cURL when an active FTP connection is used.
     This option accepts any value that can be cast to a valid int.
     Defaults to 60000 milliseconds.
     Available as of cURL 7.24.0.
The scope id value to use when connecting to IPv6 addresses.
     This option accepts any value that can be cast to a valid int.
     Defaults to 0.
     Available as of cURL 7.19.0.
Pass a string with the filename for cURL to use as the Alt-Svc cache file to read existing cache contents from and
     possibly also write it back to a after a transfer, unless CURLALTSVC_READONLYFILE
     is set via CURLOPT_ALTSVC_CTRL.
     Available as of PHP 8.2.0 and cURL 7.64.1.
Populate the bitmask with the correct set of features to instruct cURL how to handle Alt-Svc for the
     transfers using this handle. cURL only accepts Alt-Svc headers over HTTPS. It will also only complete
     a request to an alternative origin if that origin is properly hosted over HTTPS.
     Setting any bit will enable the alt-svc engine.
     Set to any of the
     CURLALTSVC_* constants.
     Defaults to Alt-Svc handling being disabled.
     Available as of PHP 8.2.0 and cURL 7.64.1.
Setting this option to 1 will cause FTP uploads
     to append to the remote file instead of overwriting it.
     Defaults to 0.
     Available as of cURL 7.17.0.
to automatically set the Referer: field in
     requests where it follows a Location: redirect.
     Defaults to 0.
     Available as of cURL 7.1.0.
Provides AWS V4 signature authentication on HTTP(S) header as a string.
     This option overrides any other authentication types that have been set in
     CURLOPT_HTTPAUTH. This method cannot be combined with other authentication types.
     Available as of PHP 8.2.0 and cURL 7.75.0.
This constant is no longer used as of PHP 5.5.0.
     Deprecated as of PHP 8.4.0.
The size of the buffer to use for each read. There is no guarantee
     this request will be fulfilled, however.
     This option accepts any value that can be cast to a valid int.
     Defaults to CURL_MAX_WRITE_SIZE (currently, 16kB).
     Available as of cURL 7.10.
A string with the name of a file holding one or more certificates to verify the
     peer with. This only makes sense when used in combination with
     CURLOPT_SSL_VERIFYPEER. Might require an absolute path.
     Available as of cURL 7.4.2.
A string with the name of a PEM file holding one or more certificates to verify the
     peer with. This option overrides CURLOPT_CAINFO.
     Available as of PHP 8.2.0 and cURL 7.77.0.
A string with a directory that holds multiple CA certificates.
     Use this option alongside CURLOPT_SSL_VERIFYPEER.
     Available as of cURL 7.9.8.
Sets the maximum time in seconds any in memory cached CA certificate store
     may be kept and reused for new connections.
     This option accepts any value that can be cast to a valid int.
     Defaults to 86400 (24 hours).
     Available as of PHP 8.3.0 and cURL 7.87.0
to output SSL certification information to STDERR
     on secure transfers.
     Requires CURLOPT_VERBOSE to be on to have an effect.
     Defaults to .
     Available as of cURL 7.19.1.
The number of seconds to wait while trying to connect. Use 0 to
     wait indefinitely.
     This option accepts any value that can be cast to a valid int.
     Defaults to 300.
     Available as of cURL 7.7.0.
The number of milliseconds to wait while trying to connect.
     Use 0 to wait indefinitely.
     If cURL is built to use the standard system name resolver, that
     portion of the connect will still use full-second resolution for
     timeouts with a minimum timeout allowed of one second.
     This option accepts any value that can be cast to a valid int.
     Defaults to 300000.
     Available as of cURL 7.16.2.
tells the library to perform all the required proxy authentication
     and connection setup, but no data transfer. This option is implemented for
     HTTP, SMTP and POP3.
     Defaults to .
     Available as of cURL 7.15.2.
Connect to a specific host and port instead of the URL's host and port.
     Accepts an array of strings with the format
     HOST:PORT:CONNECT-TO-HOST:CONNECT-TO-PORT.
     Available as of PHP 7.0.7 and cURL 7.49.0.
A string with the contents of the Cookie:  header to be used in the HTTP request.
     Note that multiple cookies are separated with a semicolon followed
     by a space (e.g., fruit=apple; colour=red).
     Available as of cURL 7.1.0.
A string with the name of the file containing the cookie data.
     The cookie file can be in Netscape format, or just plain HTTP-style headers dumped into a file.
     If the name is an empty string, no cookies are loaded, but cookie
     handling is still enabled.
     Available as of cURL 7.1.0.
A string with the name of a file to save all internal cookies to when
     the handle's destructor is called.
     Available as of cURL 7.9.0.
     
      
       As of PHP 8.0.0, curl_close is a no-op
       and does not destroy the handle.
       If cookies need to be written prior to the handle being automatically
       destroyed, run curl_setopt($ch, CURLOPT_COOKIELIST, "FLUSH");.
As of PHP 8.0.0, curl_close is a no-op
       and does not destroy the handle.
       If cookies need to be written prior to the handle being automatically
       destroyed, run curl_setopt($ch, CURLOPT_COOKIELIST, "FLUSH");.
A cookie string (i.e. a single line in Netscape/Mozilla format, or a regular
     HTTP-style Set-Cookie header) adds that single cookie to the internal cookie store.
     
      
       ALL
       erases all cookies held in memory
      
      
       SESS
       erases all session cookies held in memory
      
      
       FLUSH
       writes all known cookies to the file specified by CURLOPT_COOKIEJAR
      
      
       RELOAD
       loads all cookies from the files specified by CURLOPT_COOKIEFILE
      
     .
     Available as of cURL 7.14.1.
to mark this as a new cookie "session". It will force cURL
     to ignore all cookies it is about to load that are "session cookies"
     from the previous session. By default, cURL always stores and
     loads all cookies, independent if they are session cookies or not.
     Session cookies are cookies without expiry date and they are meant
     to be alive and existing for this "session" only.
     Available as of cURL 7.9.7.
to convert Unix newlines to CRLF newlines
     on transfers.
     Available as of cURL 7.1.0.
Pass a string naming a file with the concatenation of
     CRL (Certificate Revocation List) (in PEM format)
     to use in the certificate validation that occurs during the SSL exchange.
     When cURL is built to use GnuTLS,
     there is no way to influence the use of CRL passed
     to help in the verification process.
     When cURL is built with OpenSSL support,
     X509_V_FLAG_CRL_CHECK
     and X509_V_FLAG_CRL_CHECK_ALL are both set,
     requiring CRL check against all the elements of the certificate chain
     if a CRL file is passed.
     Also note that CURLOPT_CRLFILE implies
     CURLSSLOPT_NO_PARTIALCHAIN
     as of cURL 7.71.0 due to an OpenSSL bug.
     Available as of cURL 7.19.0.
A custom request method to use instead of
     GET or HEAD when doing
     a HTTP request. This is useful for doing
     DELETE or other, more obscure HTTP requests.
     Valid values are things like GET,
     POST, CONNECT and so on;
     i.e. Do not enter a whole HTTP request line here. For instance,
     entering GET /index.html HTTP/1.0\r\n\r\n
     would be incorrect.
     This option accepts a string or .
     Available as of cURL 7.1.0.
     
      
       Don't do this without making sure the server supports the custom
       request method first.
Don't do this without making sure the server supports the custom
       request method first.
A string with the default protocol to use if the URL is missing a scheme name.
     Available as of PHP 7.0.7 and cURL 7.45.0.
Setting this option to 1 will have different effects
     based on the protocol it is used with.
     FTP and SFTP based URLs will list only the names of files in a directory.
     POP3 will list the email message or messages on the POP3 server.
     For FILE, this option has no effect
     as directories are always listed in this mode.
     Using this option with CURLOPT_WILDCARDMATCH
     will prevent the latter from having any effect.
     Defaults to 0.
     Available as of cURL 7.17.0.
to not allow URLs that include a username.
     Usernames are allowed by default.
     Available as of PHP 7.3.0 and cURL 7.61.0.
The number of seconds to keep DNS entries in memory. This
     option is set to 120 (2 minutes) by default.
     This option accepts any value that can be cast to a valid int.
     Available as of cURL 7.9.3.
Set the name of the network interface that the DNS resolver should bind to.
     This must be an interface name (not an address).
     This option accepts a string or .
     Available as of PHP 7.0.7 and cURL 7.33.0
Set the local IPv4 address that the resolver should bind to.
     The argument should contain a single numerical IPv4 address.
     This option accepts a string or .
     Available as of PHP 7.0.7 and cURL 7.33.0.
Set the local IPv6 address that the resolver should bind to.
     The argument should contain a single numerical IPv6 address.
     This option accepts a string or .
     Available as of PHP 7.0.7 and cURL 7.33.0.
Pass a string with a comma-separated list of DNS servers to be used
     instead of the system default
     (e.g.: 192.168.1.100,192.168.1.101:8080).
     Available as of cURL 7.24.0.
to shuffle the order of all returned addresses so that they will be used
     in a random order, when a name is resolved and more than one IP address is returned.
     This may cause IPv4 to be used before IPv6 or vice versa.
     Available as of PHP 7.3.0 and cURL 7.60.0.
to use a global DNS cache. This option is not thread-safe.
     It is conditionally enabled by default if PHP is built for non-threaded use
     (CLI, FCGI, Apache2-Prefork, etc.).
     Available as of cURL 7.9.3 and deprecated as of cURL 7.11.1.
     As of PHP 8.4, this option no longer has any effect.
Set to 2 to verify the DNS-over-HTTPS server's SSL certificate name fields against the host name.
     Available as of PHP 8.2.0 and cURL 7.76.0.
Set to 1 to enable and 0 to disable
     verification of the authenticity of the DNS-over-HTTPS server's SSL certificate.
     Available as of PHP 8.2.0 and cURL 7.76.0.
Set to 1 to enable and 0 to disable
     the verification of the status of the DNS-over-HTTPS server certificate
     using the "Certificate Status Request" TLS extension (OCSP stapling).
     Available as of PHP 8.2.0 and cURL 7.76.0.
Provides the DNS-over-HTTPS URL.
     This option accepts a string or .
     Available as of PHP 8.1.0 and cURL 7.62.0.
Like CURLOPT_RANDOM_FILE, except a filename
     to an Entropy Gathering Daemon socket.
     Available as of cURL 7.7.0 and deprecated as of cURL 7.84.0.
The contents of the Accept-Encoding:  header as a string.
     This enables decoding of the response. Supported encodings are:
     
      identity
      deflate
      gzip
     .
     If an empty string is set,
     a header containing all supported encoding types is sent.
     Available as of cURL 7.10 and deprecated as of cURL 7.21.6.
The timeout for Expect: 100-continue responses in milliseconds.
     Defaults to 1000 milliseconds.
     This option accepts any value that can be cast to a valid int.
     Available as of PHP 7.0.7 and cURL 7.36.0.
to fail verbosely if the HTTP code returned
     is greater than or equal to 400. The default behavior is to return
     the page normally, ignoring the code.
     Available as of cURL 7.1.0.
Accepts a file handle resource
     to the file that the transfer should be written to.
     The default is STDOUT (the browser window).
     Available as of cURL 7.1.0 and deprecated as of cURL 7.9.7.
Set to  to attempt to retrieve the modification
     date of the remote document. This value can be retrieved using
     the CURLINFO_FILETIME option with
     curl_getinfo.
     Available as of cURL 7.5.0.
Pass a callable that will be used for wildcard matching.
     The signature of the callback should be:
     
      intcallback
      resourcecurlHandle
      stringpattern
      stringstring
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       pattern
       
        
         The wildcard pattern.
        
       
      
      
       string
       
        
         The string to run the wildcard pattern matching on.
        
       
      
     
     The callback should return
     CURL_FNMATCHFUNC_MATCH if pattern matches the string,
     CURL_FNMATCHFUNC_NOMATCH if not
     or CURL_FNMATCHFUNC_FAIL if an error occurred.
     Available as of cURL 7.21.0.
The cURL handle.
The wildcard pattern.
The string to run the wildcard pattern matching on.
Set to  to follow any Location:  header that the server sends as
     part of the HTTP header.
     See also CURLOPT_MAXREDIRS.
     This constant is not available when open_basedir
     is enabled.
     Available as of cURL 7.1.0.
Set to  to force the connection to explicitly
     close when it has finished processing, and not be pooled for reuse.
     Available as of cURL 7.7.0.
Set to  to force the use of a new connection
     instead of a cached one.
     Available as of cURL 7.7.0.
Set to  to append to the remote file instead of
     overwriting it.
     Available as of cURL 7.1.0 and deprecated as of cURL 7.16.4.
An alias of
     CURLOPT_TRANSFERTEXT. Use that instead.
     Available as of cURL 7.1, deprecated as of cURL 7.11.1
     and last available in cURL 7.15.5.
     Removed as of PHP 7.3.0.
Set to  to only list the names of an FTP directory.
     Available as of cURL 7.1.0 and deprecated as of cURL 7.16.4.
A string which will be used to get the IP address to use for the FTP PORT instruction. The PORT instruction tells
     the remote server to connect to our specified IP address.  The
     string may be a plain IP address, a hostname,
     a network interface name (under Unix),
     or just a plain - to use the system's default IP address.
     This option accepts a string or .
     Available as of cURL 7.1.0.
Set the FTP over SSL authentication method (if activated) to any of the
     CURLFTPAUTH_* constants.
     Defaults to CURLFTPAUTH_DEFAULT.
     Available as of cURL 7.12.2.
Pass a string that will be sent as account information over FTP
     (using the ACCT command) after username and password has been provided
     to the server.
     Set to  to disable sending the account information.
     Defaults to .
     Available as of cURL 7.13.0.
Pass a string that will be used to try to authenticate over FTP
     if the USER/PASS negotiation fails.
     Available as of cURL 7.15.5.
Set to  to create missing directories when an FTP operation
     encounters a path that currently doesn't exist.
     Available as of cURL 7.10.7.
Tell cURL which method to use to reach a file on a FTP(S) server. Possible values are
     any of the CURLFTPMETHOD_* constants.
     Defaults to CURLFTPMETHOD_MULTICWD.
     Available as of cURL 7.15.1.
A timeout in seconds cURL will wait for a response from an FTP server.
     This option overrides CURLOPT_TIMEOUT.
     This option accepts any value that can be cast to a valid int.
     This option name is replaced with CURLOPT_SERVER_RESPONSE_TIMEOUT,
     available as of PHP 8.4.0.
     Available as of cURL 7.10.8 and deprecated as of cURL 7.85.0.
If this option is set to 1
     cURL will not use the IP address the server suggests
     in its 227-response to cURL's PASV command
     but will use the IP address it used for the connection.
     The port number received from the 227-response will not be ignored by cURL.
     Defaults to 1 as of cURL 7.74.0
     and 0 prior to that.
     Available as of cURL 7.15.0.
Available as of cURL 7.11.0 and deprecated as of cURL 7.16.4.
This option makes cURL use CCC (Clear Command Channel)
     which shuts down the SSL/TLS layer after authenticating
     making the rest of the control channel communication unencrypted.
     Use one of the CURLFTPSSL_CCC_* constants.
     Defaults to CURLFTPSSL_CCC_NONE.
     Available as of cURL 7.16.1.
Set to  to use EPRT (and LPRT) when doing active FTP downloads.
     Set to  to disable EPRT and LPRT and use PORT only.
     Available as of cURL 7.10.5.
Set to  to first try an EPSV command for FTP transfers before reverting back to PASV.
     Set to  to disable EPSV.
     Available as of cURL 7.9.2.
Set to 1 to send a PRET command
     before PASV (and EPSV).
     Has no effect when using the active FTP transfers mode.
     Defaults to 0.
     Available as of cURL 7.20.0.
Set to CURLGSSAPI_DELEGATION_FLAG
     to allow unconditional GSSAPI credential delegation.
     Set to CURLGSSAPI_DELEGATION_POLICY_FLAG
     to delegate only if the OK-AS-DELEGATE flag is set
     in the service ticket.
     Defaults to CURLGSSAPI_DELEGATION_NONE.
     Available as of cURL 7.22.0.
Head start for IPv6 for the happy eyeballs algorithm. Happy eyeballs attempts
     to connect to both IPv4 and IPv6 addresses for dual-stack hosts,
     preferring IPv6 first for timeout milliseconds.
     Defaults to CURL_HET_DEFAULT, which is currently 200 milliseconds.
     This option accepts any value that can be cast to a valid int.
     Available as of PHP 7.3.0 and cURL 7.59.0
to send an HAProxy PROXY protocol v1 header at the start of the connection.
     The default action is not to send this header.
     Available as of PHP 7.3.0 and cURL 7.60.0.
Set to  to include the headers in the output sent to the callback
     defined by CURLOPT_WRITEFUNCTION.
     Available as of cURL 7.1.0.
A callable with the following signature:
     
      intcallback
      resourcecurlHandle
      stringheaderData
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       headerData
       
        
         The header data which must be written by the callback.
        
       
      
     
     The callback should return the number of bytes written.
     Available as of cURL 7.7.2.
The cURL handle.
The header data which must be written by the callback.
Send HTTP headers to both proxy and host or separately.
     Possible values are any of the
     CURLHEADER_* constants.
     Defaults to CURLHEADER_SEPARATE as of cURL
     7.42.1, and CURLHEADER_UNIFIED prior to that.
     Available as of PHP 7.0.7 and cURL 7.37.0.
string with HSTS (HTTP Strict Transport Security) cache file name
     or  to allow HSTS without reading from or writing to any file
     and clear the list of files to read HSTS data from.
     Available as of PHP 8.2.0 and cURL 7.74.0.
Accepts a bitmask of HSTS (HTTP Strict Transport Security) features
     defined by the CURLHSTS_* constants.
     Available as of PHP 8.2.0 and cURL 7.74.0.
Whether to allow HTTP/0.9 responses. Defaults to  as of cURL 7.66.0;
     formerly it defaulted to .
     Available as of PHP 7.3.15 and 7.4.3, respectively, and cURL 7.64.0.
An array of HTTP 200 responses that will be treated as valid responses and not as errors.
     Available as of cURL 7.10.3.
A bitmask of HTTP authentication method(s) to use. The options are:
     
      CURLAUTH_BASIC
      CURLAUTH_DIGEST
      CURLAUTH_GSSNEGOTIATE
      CURLAUTH_NTLM
      CURLAUTH_AWS_SIGV4
      CURLAUTH_ANY
      CURLAUTH_ANYSAFE
     .
     If more than one method is used, cURL will poll the server to see
     what methods it supports and pick the best one.
     CURLAUTH_ANY sets all bits. cURL will automatically select
     the one it finds most secure.
     CURLAUTH_ANYSAFE sets all bits except CURLAUTH_BASIC.
     cURL will automatically select the one it finds most secure.
     Available as of cURL 7.10.6.
Set to  to reset the HTTP request method to GET. Since GET is the default, this is only necessary if the request
     method has been changed.
     Available as of cURL 7.8.1.
An array of HTTP header fields to set, in the format
     
      array('Content-type: text/plain', 'Content-length: 100')
     
     Available as of cURL 7.1.0.
to tunnel through a given HTTP proxy.
     Available as of cURL 7.3.0.
to get the raw HTTP response body.
     Available as of cURL 7.16.2.
If set to 0, transfer decoding is disabled.
     If set to 1, transfer decoding is enabled.
     cURL does chunked transfer decoding by default
     unless this option is set to 0.
     Defaults to 1.
     Available as of cURL 7.16.2.
Set to one of the
     CURL_HTTP_VERSION_* constants
     for cURL to use the specified HTTP version.
     Available as of cURL 7.9.1.
If set to 1,
     ignore the Content-Length header in the HTTP response
     and ignore asking for or relying on it for FTP transfers.
     Defaults to 0.
     Available as of cURL 7.14.1.
Accepts a file handle resource
     to the file that the transfer should be read from when uploading.
     Available as of cURL 7.1.0 and deprecated as of cURL 7.9.7.
     Use CURLOPT_READDATA instead.
The expected size, in bytes, of the file when uploading a file to
     a remote site. Note that using this option will not stop cURL
     from sending more data, as exactly what is sent depends on
     CURLOPT_READFUNCTION.
     This option accepts any value that can be cast to a valid int.
     Available as of cURL 7.1.0.
Set to a string with the name of the outgoing network interface to use.
     This can be an interface name, an IP address or a host name.
     Available as of cURL 7.1.0.
Allows an application to select what kind of IP addresses to use when
     resolving host names. This is only interesting when using host names that
     resolve addresses using more than one version of IP.
     Set to one of the
     CURL_IPRESOLVE_* constants.
     Defaults to CURL_IPRESOLVE_WHATEVER.
     Available as of cURL 7.10.8.
If set to a string naming a file holding a CA certificate in PEM format,
     an additional check against the peer certificate is performed
     to verify the issuer is indeed the one associated
     with the certificate provided by the option.
     For the result of the check to be considered a failure,
     this option should be used in combination with the
     CURLOPT_SSL_VERIFYPEER option.
     Available as of cURL 7.19.0.
Pass a string with binary data of a CA SSL certificate in PEM format.
     If set, an additional check against the peer certificate is performed
     to verify the issuer is the one associated with the certificate provided by the option.
     Available as of PHP 8.1.0 and cURL 7.71.0.
Set to  to keep sending the request body if the HTTP code returned is equal to or larger than 300.
     The default action would be to stop sending
     and close the stream or connection. Suitable for manual NTLM authentication.
     Most applications do not need this option.
     Available as of PHP 7.3.0 and cURL 7.51.0.
Set to a string with the password required to use the CURLOPT_SSLKEY
     or CURLOPT_SSH_PRIVATE_KEYFILE private key.
     Setting this option to  disables using a password for these options.
     Available as of cURL 7.17.0.
The KRB4 (Kerberos 4) security level. Any of the following string values
     (in order from least to most powerful) are valid:
     
      clear
      safe
      confidential
      private
     .
     If the string does not match one of these,
     private is used. Setting this option to 
     will disable KRB4 security. Currently KRB4 security only works
     with FTP transactions.
     Available as of cURL 7.3.0 and deprecated as of cURL 7.17.0.
Set the kerberos security level for FTP and also enables kerberos awareness.
     This should be set to one of the following strings:
     
      clear
      safe
      confidential
      private
     .
     If the string is set but does not match one of these,
     private is used.
     Setting this option to  will disable kerberos support for FTP.
     Defaults to .
     Available as of cURL 7.16.4.
Sets the local port number of the socket used for the connection.
     This option accepts any value that can be cast to a valid int.
     Defaults to 0.
     Available as of cURL 7.15.2.
The number of attempts cURL makes to find a working local port number,
     starting with the one set with CURLOPT_LOCALPORT.
     This option accepts any value that can be cast to a valid int.
     Defaults to 1.
     Available as of cURL 7.15.2.
Can be used to set protocol specific login options, such as the
     preferred authentication mechanism via AUTH=NTLM or AUTH=*, and should be used in conjunction with the
     CURLOPT_USERNAME option.
     Available as of PHP 7.0.7 and cURL 7.34.0.
The transfer speed, in bytes per second, that the transfer should be
     below during the count of CURLOPT_LOW_SPEED_TIME
     seconds before PHP considers the transfer too slow and aborts.
     This option accepts any value that can be cast to a valid int.
     Available as of cURL 7.1.0.
The number of seconds the transfer speed should be below
     CURLOPT_LOW_SPEED_LIMIT before PHP considers
     the transfer too slow and aborts.
     This option accepts any value that can be cast to a valid int.
     Available as of cURL 7.1.0.
Set a string with the authentication address (identity)
     of a submitted message that is being relayed to another server.
     The address should not be specified within a pair of angled brackets
     ().
     If an empty string is used then a pair of brackets are sent by cURL
     as required by RFC 2554.
     Available as of cURL 7.25.0.
Set a string with the sender's email address when sending SMTP mail.
     The email address should be specified with angled brackets
     () around it,
     which if not specified are added automatically.
     If this parameter is not specified then an empty address is sent
     to the SMTP server which might cause the email to be rejected.
     Available as of cURL 7.20.0.
Set to an array of strings
     with the recipients to pass to the server in an SMTP mail request.
     Each recipient should be specified within a pair of angled brackets
     ().
     If an angled bracket is not used as the first character,
     cURL assumes a single email address has been provided
     and encloses that address within brackets.
     Available as of cURL 7.20.0.
Set to 1 to allow RCPT TO command
     to fail for some recipients which makes cURL ignore errors
     for individual recipients and proceed with the remaining accepted recipients.
     If all recipients trigger failures and this flag is specified,
     cURL aborts the SMTP conversation
     and returns the error received from to the last RCPT TO command.
     Replaced by CURLOPT_MAIL_RCPT_ALLOWFAILS as of cURL 8.2.0.
     Available as of PHP 8.2.0 and cURL 7.69.0.
     Deprecated as of cURL 8.2.0.
The maximum idle time allowed for an existing connection to be considered for reuse.
     Default maximum age is set to 118 seconds.
     This option accepts any value that can be cast to a valid int.
     Available as of PHP 8.2.0 and cURL 7.65.0.
The maximum amount of persistent connections that are allowed.
     When the limit is reached, the oldest one in the cache is closed
     to prevent increasing the number of open connections.
     This option accepts any value that can be cast to a valid int.
     Available as of cURL 7.7.0.
Sets the maximum accepted size (in bytes) of a file to download.
     If the file requested is found larger than this value,
     the transfer is aborted
     and CURLE_FILESIZE_EXCEEDED is returned.
     Passing 0 disables this option,
     and passing a negative size returns a
     CURLE_BAD_FUNCTION_ARGUMENT.
     If the file size is not known prior to the start of download,
     this option has no effect.
     For setting a size limit above 2GB,
     CURLOPT_MAXFILESIZE_LARGE should be used.
     As of cURL 8.4.0, this option also stops ongoing transfers
     if they reach this threshold.
     This option accepts any value that can be cast to a valid int.
     Defaults to 0.
     Available as of cURL 7.10.8.
The maximum file size in bytes allowed to download. If the file requested is found larger than this value,
     the transfer will not start and CURLE_FILESIZE_EXCEEDED will be returned.
     The file size is not always known prior to download, and for such files this option has no effect even if
     the file transfer ends up being larger than this given limit.
     This option accepts any value that can be cast to a valid int.
     Available as of PHP 8.2.0 and cURL 7.11.0.
The maximum time in seconds, since the creation of the connection, that is allowed for an existing
     connection to have for it to be considered for reuse. If a connection is found in the cache that is older
     than this value, it will instead be closed once any in-progress transfers are complete.
     Default is 0 seconds, meaning the option is disabled and all connections are eligible for reuse.
     This option accepts any value that can be cast to a valid int.
     Available as of PHP 8.2.0 and cURL 7.80.0.
The maximum amount of HTTP redirections to follow. Use this option alongside CURLOPT_FOLLOWLOCATION.
     Default value of 20 is set to prevent infinite redirects.
     Setting to -1 allows inifinite redirects, and 0 refuses all redirects.
     Available as of cURL 7.5.0.
If a download exceeds this speed (counted in bytes per second) on
     cumulative average during the transfer, the transfer will pause to
     keep the average rate less than or equal to the parameter value.
     Defaults to unlimited speed.
     This option accepts any value that can be cast to a valid int.
     Available as of cURL 7.15.5.
If an upload exceeds this speed (counted in bytes per second) on
     cumulative average during the transfer, the transfer will pause to
     keep the average rate less than or equal to the parameter value.
     Defaults to unlimited speed.
     This option accepts any value that can be cast to a valid int.
     Available as of cURL 7.15.5.
Set to a bitmask of CURLMIMEOPT_*
     constants. Currently there is only one available option:
     CURLMIMEOPT_FORMESCAPE.
     Available as of PHP 8.3.0 and cURL 7.81.0.
Set to  to be completely silent with regards to
     the cURL functions.
     Use CURLOPT_RETURNTRANSFER instead.
     Available as of cURL 7.1.0, deprecated as of cURL 7.8.0
     and last available in cURL 7.15.5.
     Removed as of PHP 7.3.0.
Set to  to scan the ~/.netrc
     file to find a username and password for the remote site that
     a connection is being established with.
     Available as of cURL 7.1.0.
Set a string containing the full path name to a .netrc file.
     If this option is omitted and CURLOPT_NETRC is set,
     cURL checks for a .netrc file
     in the current user's home directory.
     Available as of cURL 7.11.0.
Sets the value of the permissions (int) that is set on newly created directories
     on the remote server. The default value is 0755.
     The only protocols that can use this are
     sftp://, scp://
     and file://.
     Available as of cURL 7.16.4.
Sets the value of the permissions (as an int) that are set on newly created files
     on the remote server. The default value is 0644.
     The only protocols that can use this are
     sftp://, scp://
     and file://.
     Available as of cURL 7.16.4.
Set to  to exclude the body from the output.
     For HTTP(S), cURL makes a HEAD request. For most other protocols,
     cURL is not asking for the body data at all.
     Changing this to  will result in body data being included in the output.
     Available as of cURL 7.1.0.
Set to  to disable the progress meter for cURL transfers.
     
      
       PHP automatically sets this option to , this should only be
       changed for debugging purposes.
      
     
     Available as of cURL 7.1.0.
PHP automatically sets this option to , this should only be
       changed for debugging purposes.
Set a string consisting of a comma separated list of hostnames
     that do not require a proxy to get reached.
     Each name in this list is matched as either a domain
     which contains the hostname or the hostname itself.
     The only wildcard available in the string
     is a single * character which matches all hosts,
     effectively disabling the proxy.
     Setting this option to an empty string enables the proxy for all hostnames.
     Since cURL 7.86.0, IP addresses set with this option
     can be provided using CIDR notation.
     Available as of cURL 7.19.4.
to ignore any cURL function that causes a
     signal to be sent to the PHP process. This is turned on by default
     in multi-threaded SAPIs so timeout options can still be used.
     Available as of cURL 7.10.
A callable with the following signature:
     
      stringcallback
      resourcecurlHandle
      stringpasswordPrompt
      intmaximumPasswordLength
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       passwordPrompt
       
        
         A password prompt.
        
       
      
      
       maximumPasswordLength
       
        
         The maximum length of the password.
        
       
      
     
     The callback should return a string containing the password.
     Available as of cURL 7.4.2, deprecated as of cURL 7.11.1
     and last available in cURL 7.15.5.
     Removed as of PHP 7.3.0.
The cURL handle.
A password prompt.
The maximum length of the password.
Set to a string with the password to use in authentication.
     Available as of cURL 7.19.1.
Set to  for cURL not alter URL paths before passing them on to the server.
     Defaults to , which squashes sequences of /../
     or /./ that may exist in the URL's path part
     which is supposed to be removed according to RFC 3986 section 5.2.4.
     Available as of PHP 7.0.7 and cURL 7.42.0.
Set a string with the pinned public key.
     The string can be the file name of the pinned public key
     in a PEM or DER file format. The string can also be any
     number of base64 encoded sha256 hashes preceded by sha256// and
     separated by ;.
     Available as of PHP 7.0.7 and cURL 7.39.0.
Set to  to wait for an existing connection to confirm
     whether it can do multiplexing and use it if it can
     before creating and using a new connection.
     Available as of PHP 7.0.7 and cURL 7.43.0.
An int with an alternative port number to connect to
     instead of the one specified in the URL or the default port for the used protocol.
     Available as of cURL 7.1.0.
Set to  to do a HTTP POST request.
     This request uses the application/x-www-form-urlencoded header.
     Defaults to .
     Available as of cURL 7.1.0.
The full data to post in a HTTP POST operation.
     This parameter can either be
     passed as a urlencoded string like 'para1=val1para2=val2...'
     or as an array with the field name as key and field data as value.
     If value is an array, the
     Content-Type header will be set to
     multipart/form-data.
     Files can be sent using CURLFile or CURLStringFile,
     in which case value must be an array.
     Available as of cURL 7.1.0.
An array of FTP command strings
     to execute on the server after the FTP request has been performed.
     Available as of cURL 7.1.0.
Set to a bitmask of CURL_REDIR_POST_301,
     CURL_REDIR_POST_302 and CURL_REDIR_POST_303
     if the HTTP POST method should be maintained
     when CURLOPT_FOLLOWLOCATION is set and a
     specific type of redirect occurs.
     Available as of cURL 7.19.1.
Set a string holding the host name or dotted numerical
     IP address to be used as the preproxy that cURL connects to before
     it connects to the HTTP(S) proxy specified in the
     CURLOPT_PROXY option for the upcoming request.
     The preproxy can only be a SOCKS proxy and it should be prefixed with
     [scheme]:// to specify which kind of socks is used.
     A numerical IPv6 address must be written within [brackets].
     Setting the preproxy to an empty string explicitly disables the use of a preproxy.
     To specify port number in this string, append :[port]
     to the end of the host name. The proxy's port number may optionally be
     specified with the separate option CURLOPT_PROXYPORT.
     Defaults to using port 1080 for proxies if a port is not specified.
     Available as of PHP 7.3.0 and cURL 7.52.0.
Set an array of FTP command strings to pass to the server
     after the transfer type is set.
     These commands are not performed when a directory listing is performed,
     only for file transfers.
     Available as of cURL 7.9.5.
Any data that should be associated with this cURL handle. This data
     can subsequently be retrieved with the
     CURLINFO_PRIVATE option of
     curl_getinfo. cURL does nothing with this data.
     When using a cURL multi handle, this private data is typically a
     unique key to identify a standard cURL handle.
     Available as of cURL 7.10.3.
A callable with the following signature:
     
      intcallback
      resourcecurlHandle
      intbytesToDownload
      intbytesDownloaded
      intbytesToUpload
      intbytesUploaded
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       bytesToDownload
       
        
         The total number of bytes expected to be downloaded in this transfer.
        
       
      
      
       bytesDownloaded
       
        
         The number of bytes downloaded so far.
        
       
      
      
       bytesToUpload
       
        
         The total number of bytes expected to be uploaded in this transfer.
        
       
      
      
       bytesUploaded
       
        
         The number of bytes uploaded so far.
        
       
      
     
     The callback should return an int with a non-zero value to abort the transfer
     and set a CURLE_ABORTED_BY_CALLBACK error.
     
      
       The callback is only called when the CURLOPT_NOPROGRESS
       option is set to .
      
     
     Available as of cURL 7.1.0 and deprecated as of cURL 7.32.0.
     Use CURLOPT_XFERINFOFUNCTION instead.
The cURL handle.
The total number of bytes expected to be downloaded in this transfer.
The number of bytes downloaded so far.
The total number of bytes expected to be uploaded in this transfer.
The number of bytes uploaded so far.
The callback is only called when the CURLOPT_NOPROGRESS
       option is set to .
Bitmask of CURLPROTO_* values.
     If used, this bitmask limits what protocols cURL may use in the transfer.
     Defaults to CURLPROTO_ALL, ie. cURL will accept all protocols it supports.
     See also CURLOPT_REDIR_PROTOCOLS.
     Available as of cURL 7.19.4 and deprecated as of cURL 7.85.0.
Set to a string with a comma separated list
     of case insensitive protocol names (URL schemes) to allow in the transfer.
     Set to ALL to enable all protocols.
     By default, cURL accepts all protocols it was built with support for.
     Available protocols are:
     
      DICT
      FILE
      FTP
      FTPS
      GOPHER
      GOPHERS
      HTTP
      HTTPS
      IMAP
      IMAPS
      LDAP
      LDAPS
      MQTT
      POP3
      POP3S
      RTMP
      RTMPE
      RTMPS
      RTMPT
      RTMPTE
      RTMPTS
      RTSP
      SCP
      SFTP
      SMB
      SMBS
      SMTP
      SMTPS
      TELNET
      TFTP
      WS
      WSS
     .
     Available as of PHP 8.3.0 and cURL 7.85.0.
A string with the HTTP proxy to tunnel requests through.
     This should be the hostname, the dotted numerical IP address
     or a numerical IPv6 address written within [brackets].
     Available as of cURL 7.1.0.
A bitmask of the HTTP authentication method(s)
     (CURLAUTH_* constants)
     to use for the proxy connection.
     For proxy authentication, only CURLAUTH_BASIC and
     CURLAUTH_NTLM are currently supported.
     Defaults to CURLAUTH_BASIC.
     Available as of cURL 7.10.7.
An array of custom HTTP header strings to pass to proxies.
     Available as of PHP 7.0.7 and cURL 7.37.0.
Set a string with the password to be used for authentication with the proxy.
     Available as of cURL 7.19.1.
An int with the port number of the proxy to connect to.
     This port number can also be set in CURLOPT_PROXY.
     Setting this to zero makes cURL use the default proxy port number
     or the port number specified in the proxy URL string.
     Available as of cURL 7.1.0.
Sets the type of the proxy to one of the
     CURLPROXY_* constants.
     Defaults to CURLPROXY_HTTP.
     Available as of cURL 7.10.
Set a string with the username to be used for authentication with the proxy.
     Available as of cURL 7.19.1.
A string with a username and password formatted as
     [username]:[password] to use for the
     connection to the proxy.
     Available as of cURL 7.1.0.
The path to proxy Certificate Authority (CA) bundle. Set the path as a
     string naming a file holding one or more certificates to
     verify the HTTPS proxy with.
     This option is for connecting to an HTTPS proxy, not an HTTPS server.
     Defaults set to the system path where cURL's cacert bundle is assumed
     to be stored.
     Available as of PHP 7.3.0 and cURL 7.52.0.
A string with the name of a PEM file holding one or more certificates to verify the HTTPS proxy with.
     This option is for connecting to an HTTPS proxy, not an HTTPS server.
     Defaults set to the system path where cURL's cacert bundle is assumed
     to be stored.
     Available as of PHP 8.2.0 and cURL 7.77.0.
A string with the directory holding multiple CA certificates
     to verify the HTTPS proxy with.
     Available as of PHP 7.3.0 and cURL 7.52.0.
Set to a string with the file name
     with the concatenation of CRL (Certificate Revocation List)
     in PEM format to use in the certificate validation that occurs during
     the SSL exchange.
     Available as of PHP 7.3.0 and cURL 7.52.0.
Proxy issuer SSL certificate filename string.
     Available as of PHP 8.1.0 and cURL 7.71.0.
A string with the proxy issuer SSL certificate.
     Available as of PHP 8.1.0 and cURL 7.71.0.
Set the string be used as the password required to use the
     CURLOPT_PROXY_SSLKEY private key.
     A passphrase is not needed to load a certificate
     but one is needed to load a private key.
     This option is for connecting to an HTTPS proxy, not an HTTPS server.
     Available as of PHP 7.3.0 and cURL 7.52.0.
Set the pinned public key for HTTPS proxy.
     The string can be the file name of the pinned public key
     which is expected to be in a PEM
     or DER file format.
     The string can also be any number of base64 encoded sha256 hashes
     preceded by sha256// and separated by ;.
     Available as of PHP 7.3.0 and cURL 7.52.0.
A string with the proxy authentication service name.
     Available as of PHP 7.0.7, cURL 7.43.0 (for HTTP proxies) and cURL 7.49.0 (for SOCKS5 proxies).
A string with the file name of the client certificate used to connect to the HTTPS proxy.
     The default format is P12 on Secure Transport and PEM on other engines,
     and can be changed with CURLOPT_PROXY_SSLCERTTYPE.
     With NSS or Secure Transport, this can also be the nickname of the certificate
     used for authentication as it is named in the security database.
     If a file from the current directory is to be used,
     it must be prefixed with ./
     in order to avoid confusion with a nickname.
     Available as of PHP 7.3.0 and cURL 7.52.0.
A string with the format of the client certificate used when connecting to an HTTPS proxy.
     Supported formats are PEM and DER, except with Secure Transport.
     OpenSSL (versions 0.9.3 and later) and Secure Transport
     (on iOS 5 or later, or OS X 10.7 or later) also support P12 for
     PKCS#12-encoded files. Defaults to PEM.
     Available as of PHP 7.3.0 and cURL 7.52.0.
A string with the SSL proxy client certificate.
     Available as of PHP 8.1.0 and cURL 7.71.0.
A string with the file name of the private key
     used for connecting to the HTTPS proxy.
     The default format is PEM and can be changed with
     CURLOPT_PROXY_SSLKEYTYPE.
     (iOS and Mac OS X only) This option is ignored if cURL was built against
     Secure Transport. Available if built with TLS enabled.
     Available as of PHP 7.3.0 and cURL 7.52.0.
A string with the format of the private key.
     Supported formats are:
     
      PEM
      DER
      ENG
     .
     Available as of PHP 7.3.0 and cURL 7.52.0.
A string with the private key for connecting to the HTTPS proxy.
     Available as of PHP 8.1.0 and cURL 7.71.0.
Set the preferred HTTPS proxy TLS version to one of the
     CURL_SSLVERSION_*
     constants.
     Defaults to CURL_SSLVERSION_DEFAULT.
     
      
       It is better to not set this option and leave the default
       CURL_SSLVERSION_DEFAULT
       which will attempt to figure out the remote SSL protocol version.
      
     
     Available as of PHP 7.3.0 and cURL 7.52.0.
It is better to not set this option and leave the default
       CURL_SSLVERSION_DEFAULT
       which will attempt to figure out the remote SSL protocol version.
A string with a colon-separated list of ciphers
     to use for the connection to the HTTPS proxy.
     When used with OpenSSL commas and spaces are also acceptable as separators,
     and !, - and +
     can be used as operators.
     Available as of PHP 7.3.0 and cURL 7.52.0.
Set proxy SSL behavior options, which is a bitmask of the
     CURLSSLOPT_* constants.
     Available as of PHP 7.3.0 and cURL 7.52.0.
Set to 2 to verify in the HTTPS proxy's certificate name fields against the proxy name.
     When set to 0 the connection succeeds regardless of the names used in the certificate.
     Use that ability with caution!
     Set to 1 in cURL 7.28.0 and earlier as a debug option.
     Set to 1 in  cURL 7.28.1 to 7.65.3 CURLE_BAD_FUNCTION_ARGUMENT is returned.
     As of cURL 7.66.0 1 and 2 is treated as the same value.
     Defaults to 2.
     In production environments the value of this option should be kept at 2.
     Available as of PHP 7.3.0 and cURL 7.52.0.
Set to  to stop cURL from verifying the peer's certificate.
     Alternate certificates to verify against can be
     specified with the CURLOPT_CAINFO option
     or a certificate directory can be specified with the
     CURLOPT_CAPATH option.
     When set to , the peer certificate verification succeeds regardless.
      by default.
     Available as of PHP 7.3.0 and cURL 7.52.0.
A string with a colon-separated list of ciphers to use for the connection to the TLS 1.3 connection to a proxy.
     This option is currently used only when cURL is built to use OpenSSL 1.1.1 or later.
     When using a different SSL backend the TLS 1.3 cipher suites can be set
     with the CURLOPT_PROXY_SSL_CIPHER_LIST option.
     Available as of PHP 7.3.0 and cURL 7.61.0.
A string with the password to use for the TLS authentication method specified with the
     CURLOPT_PROXY_TLSAUTH_TYPE option. Requires that the
     CURLOPT_PROXY_TLSAUTH_USERNAME option to also be set.
     Available as of PHP 7.3.0 and cURL 7.52.0.
The method of the TLS authentication used for the HTTPS connection.
     Supported method is SRP.
     
      
       Secure Remote Password (SRP) authentication for TLS provides mutual authentication
       if both sides have a shared secret. To use TLS-SRP, the
       CURLOPT_PROXY_TLSAUTH_USERNAME and
       CURLOPT_PROXY_TLSAUTH_PASSWORD options must also be set.
      
     
     Available as of PHP 7.3.0 and cURL 7.52.0.
Secure Remote Password (SRP) authentication for TLS provides mutual authentication
       if both sides have a shared secret. To use TLS-SRP, the
       CURLOPT_PROXY_TLSAUTH_USERNAME and
       CURLOPT_PROXY_TLSAUTH_PASSWORD options must also be set.
The username to use for the HTTPS proxy TLS authentication method specified with the
     CURLOPT_PROXY_TLSAUTH_TYPE option. Requires that the
     CURLOPT_PROXY_TLSAUTH_PASSWORD option to also be set.
     Available as of PHP 7.3.0 and cURL 7.52.0.
Set to 1 to set the transfer mode (binary or ASCII)
     for FTP transfers done via an HTTP proxy, by appending
     type=a or type=i to the URL.
     Without this setting or it being set to 0,
     CURLOPT_TRANSFERTEXT has no effect
     when doing FTP via a proxy.
     Defaults to 0.
     Available as of cURL 7.18.0.
to HTTP PUT a file. The file to PUT must
     be set with CURLOPT_READDATA and
     CURLOPT_INFILESIZE.
     Available as of cURL 7.1.0 and deprecated as of cURL 7.12.1.
Set to  for cURL to skip cleanup of resources
     when recovering from a timeout.
     This allows for a swift termination of the cURL process
     at the expense of a possible leak of associated resources.
     Available as of PHP 8.3.0 and cURL 7.87.0.
An array of FTP command strings to execute on the server prior to the FTP request.
     Available as of cURL 7.1.0.
A string with a filename to be used to seed the random number generator for SSL.
     Available as of cURL 7.7.0 and deprecated as of cURL 7.84.0.
A string with the range(s) of data to retrieve in the format X-Y where X or Y are optional. HTTP transfers
     also support several intervals, separated with commas in the format
     X-Y,N-M.
     Set to  to disable requesting a byte range.
     Available as of cURL 7.1.0.
Sets a file pointer resource that will be used by the file read function
     set with CURLOPT_READFUNCTION.
     Available as of cURL 7.9.7.
A callable with the following signature:
     
      stringcallback
      resourcecurlHandle
      resourcestreamResource
      intmaxAmountOfDataToRead
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       streamResource
       
        
         Stream resource provided to cURL through the option
     CURLOPT_READDATA.
        
       
      
      
       maxAmountOfDataToRead
       
        
         The maximum amount of data to be read.
        
       
      
     
     The callback should return a string
     with a length equal or smaller than the amount of data requested,
     typically by reading it from the passed stream resource. It should
     return an empty string to signal EOF.
     Available as of cURL 7.1.0.
The cURL handle.
Stream resource provided to cURL through the option
     CURLOPT_READDATA.
The maximum amount of data to be read.
Bitmask of CURLPROTO_* values
     which limit what protocols cURL may use in a transfer that it follows to in
     a redirect when CURLOPT_FOLLOWLOCATION is enabled.
     This allows limiting specific transfers to only be allowed to use a subset
     of protocols in redirections.
     As of cURL 7.19.4, by default cURL will allow all protocols
     except for FILE and SCP.
     Prior to cURL 7.19.4, cURL would unconditionally follow to all supported protocols.
     See also CURLOPT_PROTOCOLS for protocol constant values.
     Available as of cURL 7.19.4 and deprecated as of cURL 7.85.0.
Set to a string with a comma separated list
     of case insensitive protocol names (URL schemes)
     to allow to follow to in a redirect when
     CURLOPT_FOLLOWLOCATION is enabled.
     Set to ALL to enable all protocols.
     As of cURL 7.65.2 it defaults to FTP,
     FTPS, HTTP and HTTPS.
     From cURL 7.40.0 to 7.65.1, this defaults to all protocols except
     FILE, SCP, SMB and
     SMBS.
     Prior to cURL 7.40.0, this defaults to all protocols except
     FILE and SCP.
     Available protocols are:
     
      DICT
      FILE
      FTP
      FTPS
      GOPHER
      GOPHERS
      HTTP
      HTTPS
      IMAP
      IMAPS
      LDAP
      LDAPS
      MQTT
      POP3
      POP3S
      RTMP
      RTMPE
      RTMPS
      RTMPT
      RTMPTE
      RTMPTS
      RTSP
      SCP
      SFTP
      SMB
      SMBS
      SMTP
      SMTPS
      TELNET
      TFTP
      WS
      WSS
     .
     Available as of PHP 8.3.0 and cURL 7.85.0.
A string with the contents of the Referer: 
     header to be used in a HTTP request.
     Available as of cURL 7.1.0.
A string to use in the upcoming request
     instead of the path as extracted from the URL.
     Available as of PHP 7.3.0 and cURL 7.55.0.
Provide an array of colon-separated strings
     with custom addresses for specific host and port pairs in the following format:
     
      array(
        "example.com:80:127.0.0.1",
        "example2.com:443:127.0.0.2",
      )
     
     Available as of cURL 7.21.3.
The offset, in bytes, to resume a transfer from.
     This option accepts any value that can be cast to a valid int.
     Available as of cURL 7.1.0.
to return the transfer as a string of the
     return value of curl_exec instead of outputting
     it directly.
Set an int with the CSEQ number to issue for the next RTSP request.
     Useful if the application is resuming a previously broken connection.
     The CSEQ increments from this new number henceforth.
     Defaults to 0.
     Available as of cURL 7.20.0.
Sets the kind of RTSP request to make.
     Must be one of the CURL_RTSPREQ_*
     constants.
     Available as of cURL 7.20.0.
Set an int with the CSEQ number to expect
     for the next RTSP Server to Client request.
     This feature (listening for Server requests) is unimplemented.
     Defaults to 0.
     Available as of cURL 7.20.0.
Set a string with the value of the current RTSP Session ID for the handle.
     Once this value is set to any non- value,
     cURL returns CURLE_RTSP_SESSION_ERROR
     if the ID received from the server does not match.
     If set to , cURL automatically sets the ID
     the first time the server sets it in a response.
     Defaults to 
     Available as of cURL 7.20.0.
Sets a string with the stream URI to operate on.
     If not set, cURL defaults to operating on generic server options
     by passing * in the place of the RTSP Stream URI.
     When working with RTSP, CURLOPT_RTSP_STREAM_URI
     indicates what URL to send to the server in the request header
     while the CURLOPT_URL indicates
     where to make the connection to.
     Available as of cURL 7.20.0.
Set the Transport: header for this RTSP session.
     Available as of cURL 7.20.0.
Always , what disables support for the @ prefix for
     uploading files in CURLOPT_POSTFIELDS, which
     means that values starting with @ can be safely
     passed as fields. CURLFile may be used for
     uploads instead.
The authorization identity (authzid) string for the transfer. Only applicable to the PLAIN SASL
     authentication mechanism where it is optional. When not specified, only the authentication identity
     (authcid) as specified by the username will be sent to the server, along with the password.
     The server will derive the authzid from the authcid when not provided, which it will then use internally.
     Available as of PHP 8.2.0 and cURL 7.66.0.
to enable sending the initial response in the first packet.
     Available as of PHP 7.0.7 and cURL 7.31.0.
A string with the authentication service name.
     Available as of PHP 7.0.7 and cURL 7.43.0.
A result of curl_share_init. Makes the cURL
     handle to use the data from the shared handle.
     Available as of cURL 7.10.
The SOCKS5 authentication method(s) to use. The options are:
     
      CURLAUTH_BASIC
      CURLAUTH_GSSAPI
      CURLAUTH_NONE
     .
     When more than one method is set, cURL will poll the server to see
     what methods it supports and pick the best one.
     Defaults to CURLAUTH_BASIC|CURLAUTH_GSSAPI.
     Set the actual username and password with the CURLOPT_PROXYUSERPWD option.
     Available as of PHP 7.3.0 and cURL 7.55.0.
Set to 1 to enable and 0 to disable
     the unprotected exchange of the protection mode negotiation
     as part of the GSSAPI negotiation.
     Available as of cURL 7.19.4.
Set a string holding the name of the SOCKS5 service.
     Defaults to rcmd.
     Available as of cURL 7.19.4 and deprecated as of cURL 7.49.0.
     Use CURLOPT_PROXY_SERVICE_NAME instead.
A bitmask consisting of one or more of the following constants:
     
      CURLSSH_AUTH_PUBLICKEY
      CURLSSH_AUTH_PASSWORD
      CURLSSH_AUTH_HOST
      CURLSSH_AUTH_KEYBOARD
      CURLSSH_AUTH_AGENT
      CURLSSH_AUTH_ANY
     .
     Defaults to CURLSSH_AUTH_ANY.
     Available as of cURL 7.16.1.
to enable,  to disable built-in SSH compression.
     Note that the server can disregard this request.
     Defaults to .
     Available as of PHP 7.3.0 and cURL 7.56.0.
A callable that will be called when SSH host key verification is needed.
     The callback must have the following signature:
     
      intcallback
      resourcecurlHandle
      intkeyType
      stringkey
      intkeyLength
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       keyType
       
        
         One of the CURLKHTYPE_* key types.
        
       
      
      
       key
       
        
         The key to check.
        
       
      
      
       keyLength
       
        
         The length of the key in bytes.
        
       
      
     
     This callback overrides CURLOPT_SSH_KNOWNHOSTS.
     Available as of PHP 8.3.0 and cURL 7.84.0.
The cURL handle.
One of the CURLKHTYPE_* key types.
The key to check.
The length of the key in bytes.
A string containing 32 hexadecimal digits which should contain the
     MD5 checksum of the remote host's public key, and cURL will reject
     the connection to the host unless the md5sums match.
     This option is only for SCP and SFTP transfers.
     Available as of cURL 7.17.1.
A string with the base64-encoded SHA256 hash
     of the remote host's public key.
     The transfer will fail if the given hash does not match the hash the remote host provides.
     Available as of PHP 8.2.0 and cURL 7.80.0.
Set to the filename of the known_host file to use
     which should use the OpenSSH file format as supported by libssh2.
     Available as of cURL 7.19.6.
The file name for a private key. If not used, cURL defaults to
     $HOME/.ssh/id_dsa if the HOME environment variable is set,
     and just id_dsa in the current directory if HOME is not set.
     If the file is password-protected, set the password with
     CURLOPT_KEYPASSWD.
     Available as of cURL 7.16.1.
The file name for a public key. If not used, cURL defaults to
     $HOME/.ssh/id_dsa.pub if the HOME environment variable is set,
     and just id_dsa.pub in the current directory if HOME is not set.
     Available as of cURL 7.16.1.
The name of a file containing a PEM formatted certificate.
     Available as of cURL 7.1.0.
The password required to use the
     CURLOPT_SSLCERT certificate.
     Available as of cURL 7.1.0 and deprecated as of cURL 7.17.0.
A string with the format of the certificate. Supported formats are:
     
      PEM
      DER
      ENG
      P12
     .
     P12 (for PKCS#12-encoded files) is available as of OpenSSL 0.9.3.
     Defaults to PEM.
     Available as of cURL 7.9.3.
A string with the SSL client certificate.
     Available as of PHP 8.1.0 and cURL 7.71.0.
The string identifier for the crypto engine of the private SSL key
     specified in CURLOPT_SSLKEY.
     Available as of cURL 7.9.3.
The string identifier for the crypto engine used for asymmetric crypto
     operations.
     Available as of cURL 7.9.3.
The name of a file containing a private SSL key.
     Available as of cURL 7.9.3.
The secret password needed to use the private SSL key specified in
     CURLOPT_SSLKEY.
     
      
       Since this option contains a sensitive password, remember to keep
       the PHP script it is contained within safe.
      
     
     Available as of cURL 7.9.3 and deprecated as of cURL 7.17.0.
Since this option contains a sensitive password, remember to keep
       the PHP script it is contained within safe.
The key type of the private SSL key specified in
     CURLOPT_SSLKEY. Supported key types are:
     
      PEM
      DER
      ENG
     .
     Defaults to PEM.
     Available as of cURL 7.9.3.
A string private key for client cert.
     Available as of PHP 8.1.0 and cURL 7.71.0.
One of
     the CURL_SSLVERSION_* constants.
     
      
       It is better to not set this option and leave the defaults.
       As setting this to
       CURL_SSLVERSION_SSLv2
       or
       CURL_SSLVERSION_SSLv3
       is very dangerous, given the known
       vulnerabilities in SSLv2 and SSLv3.
      
     
     Defaults to CURL_SSLVERSION_DEFAULT.
     Available as of cURL 7.1.0.
It is better to not set this option and leave the defaults.
       As setting this to
       CURL_SSLVERSION_SSLv2
       or
       CURL_SSLVERSION_SSLv3
       is very dangerous, given the known
       vulnerabilities in SSLv2 and SSLv3.
A colon-separated string of ciphers to use
     for the TLS 1.2 (1.1, 1.0) connection.
     Available as of cURL 7.9.
A colon delimited list of elliptic curve algorithms. For example,
     X25519:P-521 is a valid list of two elliptic curves.
     This option defines the client's key exchange algorithms in the SSL handshake,
     if the SSL backend cURL is built to use supports it.
     Available as of PHP 8.2.0 and cURL 7.73.0.
to disable ALPN in the SSL handshake (if the SSL backend
     cURL is built to use supports it), which can be used to
     negotiate http2.
     Available as of PHP 7.0.7 and cURL 7.36.0.
to disable NPN in the SSL handshake (if the SSL backend
     cURL is built to use supports it), which can be used to
     negotiate http2.
     Available as of PHP 7.0.7 and cURL 7.36.0, and deprecated as of cURL 7.86.0.
to enable and  to disable TLS false start
     which is a mode where a TLS client starts sending application data
     before verifying the server's Finished message.
     Available as of PHP 7.0.7 and cURL 7.42.0.
Set SSL behavior options, which is a bitmask of the
     CURLSSLOPT_* constants.
     Defaults to none of the bits being set.
     Available as of PHP 7.0.7. and cURL 7.25.0.
Set to 0 to disable and 1 to enable
     SSL session-ID caching.
     By default all transfers are done using the cache enabled.
     Available as of cURL 7.16.0.
2 to verify that a Common Name field or a Subject Alternate Name
     field in the SSL peer certificate matches the provided hostname.
     0 to not check the names.
     1 should not be used.
     In production environments the value of this option
     should be kept at 2 (default value). Support for value 1 removed in cURL 7.28.1.
     Available as of cURL 7.8.1.
to stop cURL from verifying the peer's
     certificate. Alternate certificates to verify against can be
     specified with the CURLOPT_CAINFO option
     or a certificate directory can be specified with the
     CURLOPT_CAPATH option.
     Defaults to  as of cURL 7.10.
     Default bundle of CA certificates installed as of cURL 7.10.
     Available as of cURL 7.4.2.
to enable and  to disable verification of the certificate's status.
     Available as of PHP 7.0.7 and cURL 7.41.0.
Accepts a file handle resource pointing to
     an alternative location to output errors to instead of
     STDERR.
     Available as of cURL 7.1.0.
Set the numerical stream weight (a number between 1 and 256).
     Available as of PHP 7.0.7 and cURL 7.46.0.
to suppress proxy CONNECT response headers from the user callback functions
     CURLOPT_HEADERFUNCTION and CURLOPT_WRITEFUNCTION,
     when CURLOPT_HTTPPROXYTUNNEL is used and a CONNECT request is made.
     Defaults to .
     Available as of PHP 7.3.0 and cURL 7.54.0.
to enable and  to disable TCP Fast Open.
     Available as of PHP 7.0.7 and cURL 7.49.0.
If set to 1, TCP keepalive probes will be sent. The delay and
     frequency of these probes can be controlled by the CURLOPT_TCP_KEEPIDLE
     and CURLOPT_TCP_KEEPINTVL options, provided the operating system
     supports them. If set to 0 (default) keepalive probes are disabled.
     The maximum number of probes can be set with the CURLOPT_TCP_KEEPCNT
     option.
     Available as of cURL 7.25.0.
Sets the delay, in seconds, that the operating system will wait while the connection is
     idle before sending keepalive probes, if CURLOPT_TCP_KEEPALIVE is
     enabled. Not all operating systems support this option.
     The default is 60.
     Available as of cURL 7.25.0.
Sets the interval, in seconds, that the operating system will wait between sending
     keepalive probes, if CURLOPT_TCP_KEEPALIVE is enabled.
     Not all operating systems support this option.
     The default is 60.
     Available as of cURL 7.25.0.
Sets the maximum number of TCP keep-alive probes.
     The default is 9.
     Available as of PHP 8.4.0 and cURL 8.9.0.
to disable TCP's Nagle algorithm, which tries to minimize
     the number of small packets on the network.
     Defaults to .
     Available as of cURL 7.11.2.
Set an array of strings to pass to the telnet negotiations.
     The variables should be in the format option=value.
     cURL supports the options TTYPE,
     XDISPLOC and NEW_ENV.
     Available as of cURL 7.7.0.
Set the blocksize to use for TFTP data transmission.
     Valid range is 8-65464 bytes.
     The default of 512 bytes is used if this option is not specified.
     The specified block size is only used if supported by the remote server.
     If the server does not return an option acknowledgment
     or returns an option acknowledgment with no block size,
     the default of 512 bytes is used.
     Available as of cURL 7.19.4.
to not send TFTP options requests.
     Defaults to .
     Available as of PHP 7.0.7 and cURL 7.48.0.
Set how CURLOPT_TIMEVALUE is treated.
     Use CURL_TIMECOND_IFMODSINCE to return the
     page only if it has been modified since the time specified in
     CURLOPT_TIMEVALUE. If it hasn't been modified,
     a 304 Not Modified header will be returned
     assuming CURLOPT_HEADER is .
     Use CURL_TIMECOND_IFUNMODSINCE for the reverse
     effect. Use CURL_TIMECOND_NONE to ignore
     CURLOPT_TIMEVALUE and always return the page.
     CURL_TIMECOND_NONE is the default.
     Prior to cURL 7.46.0 the default was
     CURL_TIMECOND_IFMODSINCE.
     Available as of cURL 7.1.0.
The maximum number of seconds to allow cURL functions to execute.
     Defaults to 0, meaning that functions never time out during transfer.
     Available as of cURL 7.1.0.
The maximum number of milliseconds to allow cURL functions to
     execute.
     If cURL is built to use the standard system name resolver, that
     portion of the connect will still use full-second resolution for
     timeouts with a minimum timeout allowed of one second.
     Defaults to 0, meaning that functions never time out during transfer.
     Available as of cURL 7.16.2.
The time in seconds since January 1st, 1970. The time will be used
     by CURLOPT_TIMECONDITION.
     Defaults to 0.
     Available as of cURL 7.1.0.
The time in seconds since January 1st, 1970. The time will be used
     by CURLOPT_TIMECONDITION. Defaults to zero.
     The difference between this option and CURLOPT_TIMEVALUE
     is the type of the argument. On systems where 'long' is only 32 bit wide,
     this option has to be used to set dates beyond the year 2038.
     Available as of PHP 7.3.0 and cURL 7.59.0.
A string with a colon-separated list of ciphers
     to use for the connection to the TLS 1.3 connection.
     This option is currently used only when cURL is built to use OpenSSL 1.1.1 or later.
     When using a different SSL backend the TLS 1.3 cipher suites can be set
     with the CURLOPT_SSL_CIPHER_LIST option.
     Available as of PHP 7.3.0 and cURL 7.61.0.
Set a password to use for the TLS authentication method specified
     with the CURLOPT_TLSAUTH_TYPE option. Requires that
     the CURLOPT_TLSAUTH_USERNAME option also be set.
     This feature relies on TLS SRP which does not work with TLS 1.3.
     Available as of cURL 7.21.4.
Set a string with the method of the TLS authentication.
     Supported method is SRP
     (TLS Secure Remote Password authentication).
     Available as of cURL 7.21.4.
Set a string with the username to use for the TLS authentication method
     specified with the CURLOPT_TLSAUTH_TYPE option.
     Requires that the CURLOPT_TLSAUTH_PASSWORD option
     also be set.
     This feature relies on TLS SRP which does not work with TLS 1.3.
     Available as of cURL 7.21.4.
Set to 1 to enable and 0 to disable
     requesting compressed Transfer Encoding in the outgoing
     HTTP request. If the server responds with a compressed
     Transfer Encoding,
     cURL will automatically uncompress it on reception.
     Defaults to 0.
     Available as of cURL 7.21.6.
to use ASCII mode for FTP transfers.
     For LDAP, it retrieves data in plain text instead of HTML. On
     Windows systems, it will not set STDOUT to binary
     mode.
     Defaults to .
     Available as of cURL 7.1.1.
Enables the use of Unix domain sockets as connection endpoint and
     sets the path to the given string.
     Set to  to disable.
     Defaults to .
     Available as of PHP 7.0.7 and cURL 7.40.0.
to keep sending the username and password
     when following locations (using
     CURLOPT_FOLLOWLOCATION), even when the
     hostname has changed.
     Defaults to .
     Available as of cURL 7.10.4.
Some protocols have "connection upkeep" mechanisms. These mechanisms usually send some traffic
     on existing connections in order to keep them alive. This option defines the connection upkeep interval.
     Currently, the only protocol with a connection upkeep mechanism is HTTP/2. When the connection upkeep
     interval is exceeded, an HTTP/2 PING frame is sent on the connection.
     Defaults to CURL_UPKEEP_INTERVAL_DEFAULT
     which is currently 60 seconds.
     Available as of PHP 8.2.0 and cURL 7.62.0.
to prepare for and perform an upload.
     Defaults to .
     Available as of cURL 7.1.0.
Preferred buffer size in bytes for the cURL upload buffer.
     The upload buffer size by default is 64 kilobytes. The maximum buffer size allowed to be set is 2 megabytes.
     The minimum buffer size allowed to be set is 16 kilobytes.
     Available as of PHP 8.2.0 and cURL 7.62.0.
The URL to fetch. This can also be set when initializing a
     session with curl_init.
     Available as of cURL 7.1.0.
Sets the desired level of SSL/TLS for the transfer
     when using FTP, SMTP, POP3, IMAP, etc.
     These are all protocols that start out plain text
     and get "upgraded" to SSL using the STARTTLS command.
     Set to one of the
     CURLUSESSL_* constants.
     Available as of cURL 7.17.0.
The contents of the User-Agent:  header to be
     used in a HTTP request.
     Available as of cURL 7.1.0.
The user name to use in authentication.
     Available as of cURL 7.19.1.
A username and password formatted as
     [username]:[password] to use for the
     connection.
     Available as cURL 7.1.0.
to output verbose information. Writes
     output to STDERR, or the file specified using
     CURLOPT_STDERR.
     Defaults to .
     Available as of cURL 7.1.0.
Set to 1 to transfer multiple files
     according to a filename pattern.
     The pattern can be specified as part of the
     CURLOPT_URL option,
     using an fnmatch-like pattern (Shell Pattern Matching)
     in the last part of URL (filename).
     Available as of cURL 7.21.0.
A callable with the following signature:
     
      intcallback
      resourcecurlHandle
      stringdata
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       data
       
        
         The data to be written.
        
       
      
     
     The data must be saved by the callback
     and the callback must return the exact number of bytes written
     or the transfer will be aborted with an error.
     Available as of cURL 7.1.0.
The cURL handle.
The data to be written.
Accepts a file handle resource to the file that the header part of the transfer is written to.
     Available as of cURL 7.1.0.
Accepts a bitmask setting WebSocket behavior options.
     The only available option is CURLWS_RAW_MODE.
     Defaults to 0.
     Available as of PHP 8.3.0 and cURL 7.86.0.
A callable with the following signature:
     
      intcallback
      resourcecurlHandle
      intbytesToDownload
      intbytesDownloaded
      intbytesToUpload
      intbytesUploaded
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       bytesToDownload
       
        
         The total number of bytes expected to be downloaded in this transfer.
        
       
      
      
       bytesDownloaded
       
        
         The number of bytes downloaded so far.
        
       
      
      
       bytesToUpload
       
        
         The total number of bytes expected to be uploaded in this transfer.
        
       
      
      
       bytesUploaded
       
        
         The number of bytes uploaded so far.
        
       
      
     
     Return 1 to abort the transfer
     and set a CURLE_ABORTED_BY_CALLBACK error.
     Available as of PHP 8.2.0 and cURL 7.32.0.
The cURL handle.
The total number of bytes expected to be downloaded in this transfer.
The number of bytes downloaded so far.
The total number of bytes expected to be uploaded in this transfer.
The number of bytes uploaded so far.
A timeout in seconds cURL will wait for a response from an
     FTP, SFTP, IMAP,
     SCP, SMTP, or a POP3 server.
     This option replaces the existing CURLOPT_FTP_RESPONSE_TIMEOUT
     option which is deprecated in cURL 7.85.0.
     Available as of PHP 8.4.0.
Specifies the OAuth 2.0 access token.
     Set to  to disable.
     Defaults to .
     Available as of PHP 7.0.7 and cURL 7.33.0.
A callable with the following signature that gets called after the
     connection is established, but before the request payload (for example, the
     GET/POST/DELETE request of an HTTP connection) is sent, and can be used to abort
     or allow the connection depending on the source and destination IP address and
     port numbers:
     
      intcallback
      CurlHandlecurlHandle
      stringdestination_ip
      stringlocal_ip
      intdestination_port
      intlocal_port
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       destination_ip
       
        
         The primary IP of the remote server established with this connection.
         For FTP, this is the IP for the control connection.
         IPv6 addresses are represented without surrounding brackets.
        
       
      
      
       local_ip
       
        
         The originating IP for this connection.
         IPv6 addresses are represented without surrounding brackets.
        
       
      
      
       destination_port
       
        
         The primary port number on the remote server established with this connection.
         For FTP, this is the port for the control connection.
         This can be a TCP or a UDP port number depending on the protocol.
        
       
      
      
       local_port
       
        
         The originating port number for this connection.
         This can be a TCP or a UDP port number depending on the protocol.
        
       
      
     
     Return CURL_PREREQFUNC_OK to allow the request, or
     CURL_PREREQFUNC_ABORT to abort the transfer.
     Available as of PHP 8.4.0 and cURL 7.80.0.
The cURL handle.
The primary IP of the remote server established with this connection.
         For FTP, this is the IP for the control connection.
         IPv6 addresses are represented without surrounding brackets.
The originating IP for this connection.
         IPv6 addresses are represented without surrounding brackets.
The primary port number on the remote server established with this connection.
         For FTP, this is the port for the control connection.
         This can be a TCP or a UDP port number depending on the protocol.
The originating port number for this connection.
         This can be a TCP or a UDP port number depending on the protocol.
Available as of PHP 8.4.0.
     This option requires CURLOPT_VERBOSE option enabled.
     A callable to replace the standard cURL verbose output.
     This callback gets called during various stages of the request with verbose debug information.
     The callback should match the following signature:
     
      voidcallback
      CurlHandlecurlHandle
      inttype
      stringdata
     
     
      
       curlHandle
       
        
         The cURL handle.
        
       
      
      
       type
       
        
         One of the following constants indicating the type of the data value:
        
        
         
          
           CURLINFO_TEXT
           (int)
          
          
           
            Informational text.
           
          
         
         
          
           CURLINFO_HEADER_IN
           (int)
          
          
           
            Header (or header-like) data received from the peer.
           
          
         
         
          
           CURLINFO_HEADER_OUT
           (int)
          
          
           
            Header (or header-like) data sent to the peer.
           
          
         
         
          
           CURLINFO_DATA_IN
           (int)
          
          
           
            Unprocessed protocol data received from the peer.
            Even if the data is encoded or compressed, it is not provided decoded nor decompressed to this callback.
           
          
         
         
          
           CURLINFO_DATA_OUT
           (int)
          
          
           
            Protocol data sent to the peer.
           
          
         
         
          
           CURLINFO_SSL_DATA_IN
           (int)
          
          
           
            SSL/TLS (binary) data received from the peer.
           
          
         
         
          
           CURLINFO_SSL_DATA_OUT
           (int)
          
          
           
            SSL/TLS (binary) data sent to the peer.
           
          
         
        
       
      
      
       data
       
        
         Verbose debug data of the type indicate by the type parameter.
The cURL handle.
One of the following constants indicating the type of the data value:
Informational text.
Header (or header-like) data received from the peer.
Header (or header-like) data sent to the peer.
Unprocessed protocol data received from the peer.
            Even if the data is encoded or compressed, it is not provided decoded nor decompressed to this callback.
Protocol data sent to the peer.
SSL/TLS (binary) data received from the peer.
SSL/TLS (binary) data sent to the peer.
Verbose debug data of the type indicate by the type parameter.
cURL protocol constants
Available as of cURL 7.19.4.
Available as of cURL 7.19.4.
Available as of cURL 7.19.4.
Available as of cURL 7.19.4.
Available as of cURL 7.19.4.
Available as of cURL 7.21.2.
Available as of cURL 7.19.4.
Available as of cURL 7.19.4.
Available as of cURL 7.20.0.
Available as of cURL 7.20.0.
Available as of cURL 7.19.4.
Available as of cURL 7.19.4.
Available as of PHP 8.2.0 and cURL 7.71.0.
Available as of cURL 7.20.0.
Available as of cURL 7.20.0.
Available as of cURL 7.21.0.
Available as of cURL 7.21.0.
Available as of cURL 7.21.0.
Available as of cURL 7.21.0.
Available as of cURL 7.21.0.
Available as of cURL 7.21.0.
Available as of cURL 7.20.0.
Available as of cURL 7.19.4.
Available as of cURL 7.19.4.
Available as of PHP 7.0.7 and cURL 7.40.0.
Available as of PHP 7.0.7 and cURL 7.40.0.
Available as of cURL 7.20.0.
Available as of cURL 7.20.0.
Available as of cURL 7.19.4.
Available as of cURL 7.19.4.
curl_share_setopt
Shares/unshares the connection cache.
    Available as of PHP 7.3.0 and cURL 7.10.3.
Shares/unshares cookie data.
    Available as of cURL 7.10.3.
Shares/unshares DNS cache.
    Note that when you use cURL multi handles,
    all handles added to the same multi handle will share DNS cache by default.
    Available as of cURL 7.10.3.
Shares/unshares the Public Suffix List.
    Available as of PHP 7.3.0 and cURL 7.61.0.
Shares/unshares SSL session IDs, reducing the time spent
    on the SSL handshake when reconnecting to the same server.
    Note that SSL session IDs are reused within the same handle by default.
    Available as of cURL 7.10.3.
Available as of cURL 7.10.3.
Specifies a type of data that should be shared.
    Available as of cURL 7.10.3.
Specifies a type of data that will be no longer shared.
    Available as of cURL 7.10.3.
curl_multi_* status constants
An easy handle already added to a multi handle was attempted to get added a second time.
    Available as of cURL 7.32.1.
An easy handle was not good/valid. It could mean that it is not an easy handle at all, or possibly that the handle already is in use by this or another multi handle.
    Available as of cURL 7.9.6.
The passed-in handle is not a valid multi handle.
    Available as of cURL 7.9.6.
As of cURL 7.20.0, this constant is not used.
    Before cURL 7.20.0, this status could be returned by
    curl_multi_exec when curl_multi_select
    or a similar function was called before it returned any other constant.
    Available as of cURL 7.9.6.
Internal libcurl error.
    Available as of cURL 7.9.6.
No errors.
    Available as of cURL 7.9.6.
Ran out of memory while processing multi handles.
    Available as of cURL 7.9.6.
curl_getinfo
Time in seconds it took from the start until the SSL/SSH connect/handshake to the remote host was completed
Time, in microseconds, it took from the start until the SSL/SSH connect/handshake to the remote host was completed.
    Available as of PHP 7.3.0 and cURL 7.61.0
Default built-in CA certificate path.
    Available as of PHP 8.3.0 and cURL 7.84.0
Default built-in CA path string.
    Available as of PHP 8.3.0 and cURL 7.84.0
TLS certificate chain
Info on unmet time conditional
Time in seconds it took to establish the connection
Total time taken, in microseconds, from the start until the connection to the remote host (or proxy) was completed.
    Available as of PHP 7.3.0 and cURL 7.61.0
Content length of download, read from Content-Length: field
The content-length of the download. This is the value read from the Content-Length: field. -1 if the size isn't known.
    Available as of PHP 7.3.0 and cURL 7.55.0
Specified size of upload
The specified size of the upload. -1 if the size isn't known.
    Available as of PHP 7.3.0 and cURL 7.55.0
Content-Type of the requested document.
    NULL indicates server did not send valid Content-Type header
All known cookies
Get the last used HTTP method.
Last effective URL
Remote time of the retrieved document, with the CURLOPT_FILETIME enabled; if -1 is returned the time of the document is unknown
Remote time of the retrieved document (as Unix timestamp), an alternative to CURLINFO_FILETIME to allow systems with 32 bit long variables to extract dates outside of the 32bit timestamp range.
    Available as of PHP 7.3.0 and cURL 7.59.0
Entry path in FTP server
The request string sent. For this to work, add the CURLINFO_HEADER_OUT option to the handle by calling curl_setopt
Total size of all headers received
Bitmask indicating the authentication method(s) available according to the previous response
The last response code.
    As of cURL 7.10.8, this is a legacy alias of CURLINFO_RESPONSE_CODE.
The CONNECT response code
The version used in the last HTTP connection. The return value will be one of the defined CURL_HTTP_VERSION_* constants or 0 if the version can't be determined.
    Available as of PHP 7.3.0 and cURL 7.50.0
The last enum value in the underlying CURLINFO enum
    in libcurl.
Local (source) IP address of the most recent connection
Local (source) port of the most recent connection
Time in seconds until name resolving was complete
Time in microseconds from the start until the name resolving was completed.
    Available as of PHP 7.3.0 and cURL 7.61.0
Number of connections curl had to create to achieve the previous transfer
Errno from a connect failure. The number is OS and system specific.
Time in seconds from start until just before file transfer begins
Time taken from the start until the file transfer is just about to begin, in microseconds.
    Available as of PHP 7.3.0 and cURL 7.61.0
IP address of the most recent connection
Destination port of the most recent connection
Private data associated with this cURL handle, previously set with the CURLOPT_PRIVATE option of curl_setopt
The protocol used in the last HTTP connection. The returned value will be exactly one of the CURLPROTO_* values.
    Available as of PHP 7.3.0 and cURL 7.52.0
Bitmask indicating the proxy authentication method(s) available according to the previous response
The detailed (SOCKS) proxy error code when the most recent transfer returned a CURLE_PROXY error. The returned value will be exactly one of the CURLPX_* values. The error code will be CURLPX_OK if no response code was available.
    Available as of PHP 8.2.0 and cURL 7.73.0
The result of the certificate verification that was requested (using the CURLOPT_PROXY_SSL_VERIFYPEER option). Only used for HTTPS proxies.
    Available as of PHP 7.3.0 and cURL 7.52.0
Number of redirects, with the CURLOPT_FOLLOWLOCATION option enabled
Time in seconds of all redirection steps before final transaction was started, with the CURLOPT_FOLLOWLOCATION option enabled
Total time, in microseconds, it took for all redirection steps include name lookup, connect, pretransfer and transfer before final transaction was started.
    Available as of PHP 7.3.0 and cURL 7.61.0
With the CURLOPT_FOLLOWLOCATION option disabled: redirect URL found in the last transaction, that should be requested manually next. With the CURLOPT_FOLLOWLOCATION option enabled: this is empty. The redirect URL in this case is available in CURLINFO_EFFECTIVE_URL
The Referer header.
    Available as of PHP 8.2.0 and cURL 7.76.0
Total size of issued requests, currently only for HTTP requests
The last response code.
    Available as of cURL 7.10.8
The information from the Retry-After header, or zero if there was no valid header.
    Available as of PHP 8.2.0 and cURL 7.66.0
Next RTSP client CSeq
Recently received CSeq
Next RTSP server CSeq
RTSP session ID
The URL scheme used for the most recent connection.
    Available as of PHP 7.3.0 and cURL 7.52.0
Total number of bytes downloaded
Total number of bytes that were downloaded. The number is only for the latest transfer and will be reset again for each new transfer.
    Available as of PHP 7.3.0 and cURL 7.50.0
Total number of bytes uploaded
Total number of bytes that were uploaded.
    Available as of PHP 7.3.0 and cURL 7.50.0
Average download speed
The average download speed in bytes/second that curl measured for the complete download.
    Available as of PHP 7.3.0 and cURL 7.50.0
Average upload speed
The average upload speed in bytes/second that curl measured for the complete upload.
    Available as of PHP 7.3.0 and cURL 7.50.0
OpenSSL crypto-engines supported
Result of SSL certification verification requested by setting CURLOPT_SSL_VERIFYPEER
Time in seconds until the first byte is about to be transferred
Time, in microseconds, it took from the start until the first byte is received.
    Available as of PHP 7.3.0 and cURL 7.61.0
Total transaction time in seconds for last transfer
Total time in microseconds for the previous transfer, including name resolving, TCP connect etc.
    Available as of PHP 7.3.0 and cURL 7.61.0
Time it took from the start until the last byte is sent, in microseconds.
    Available as of PHP 8.4.0 and cURL 8.10.0
cURL error constants
Aborted by callback. A callback returned "abort" to libcurl.
Unrecognized transfer encoding.
The download could not be resumed because the specified offset was out of the file boundary.
A function was called with a bad parameter.
Failed to connect to host or proxy.
Could not resolve host. The given remote host was not resolved.
Could not resolve proxy. The given proxy host could not be resolved.
Early initialization code failed.
    This is likely to be an internal error or problem,
    or a resource problem where something fundamental could not get done at init time.
Maximum file size exceeded.
A file given with FILE:// could not be opened.
    Most likely because the file path does not identify an existing file
    or due to the lack of appropriate file permissions.
An internal failure to lookup the host used for the new connection.
This was either a unexpected reply to a 'RETR' command
    or a zero byte transfer complete.
The FTP REST command returned error.
    This should never happen if the server is sane.
The FTP PORT command returned error.
    This mostly happens when a good enough address has not been specified for libcurl to use.
    See CURLOPT_FTPPORT.
FTP servers return a 227-line as a response to a PASV command.
    If libcurl fails to parse that line, this return code is passed back.
After having sent the FTP password to the server, libcurl expects a proper reply.
    This error code indicates that an unexpected code was returned.
libcurl failed to get a sensible result back from the server
    as a response to either a PASV or a EPSV command. The server is flawed.
The server sent data libcurl could not parse.
    This error code is known as CURLE_WEIRD_SERVER_REPLY
    as of cURL 7.51.0.
Function not found. A required zlib function was not found.
Nothing was returned from the server, and under the circumstances,
    getting nothing is considered an error.
This is an odd error that mainly occurs due to internal confusion.
This is returned if CURLOPT_FAILONERROR is set 
    and the HTTP server returns an error code that is greater than or equal to 400.
LDAP cannot bind. LDAP bind operation failed.
LDAP search failed.
All fine. Proceed as usual.
Operation timeout.
    The specified time-out period was reached according to the conditions.
A memory allocation request failed.
A file transfer was shorter or larger than expected.
    This happens when the server first reports an expected transfer size,
    and then delivers data that does not match the previously given size.
Proxy handshake error.
    CURLINFO_PROXY_ERROR provides extra details on the specific problem.
    Available as of PHP 8.2.0 and cURL 7.73.0
There was a problem reading a local file or an error returned by the read callback.
Failure with receiving network data.
Failed sending network data.
An unspecified error occurred during the SSH session.
    Available as of cURL 7.16.1.
Problem with reading the SSL CA cert.
Problem with the local client certificate.
Could not use specified cipher.
A problem occurred somewhere in the SSL/TLS handshake.
    Reading the message in the error buffer provides more details on the problem.
    Could be certificates (file formats, paths, permissions), passwords, and others.
The specified crypto engine was not found.
Failed setting the selected SSL crypto engine as default.
Failed to match the pinned key specified with
    CURLOPT_PINNEDPUBLICKEY.
Too many redirects. When following redirects, libcurl hit the maximum amount.
    The limit can be set with CURLOPT_MAXREDIRS.
The URL passed to libcurl used a protocol that libcurl does not support.
    The issue might be a compile-time option that was not used,
    a misspelled protocol string or just a protocol libcurl has no code for.
The URL was not properly formatted.
The server sent data libcurl could not parse.
    This error code was known as CURLE_FTP_WEIRD_SERVER_REPLY
    before cURL 7.51.0.
    Available as of PHP 7.3.0 and cURL 7.51.0
An error occurred when writing received data to a local file,
    or an error was returned to libcurl from a write callback.
curl_pause
Pause sending and receiving data.
    Available as of cURL 7.18.0.
Unpause sending and receiving data.
    Available as of cURL 7.18.0.
Pause receiving data.
    Available as of cURL 7.18.0.
Unpause receiving data.
    Available as of cURL 7.18.0.
Pause sending data.
    Available as of cURL 7.18.0.
Unpause sending data.
    Available as of cURL 7.18.0.
curl_multi_setopt
Specifies the chunk length threshold for pipelining in bytes.
     Available as of PHP 7.0.7 and cURL 7.30.0
Specifies the size threshold for pipelining penalty in bytes.
     Available as of PHP 7.0.7 and cURL 7.30.0
Specifies the maximum amount of simultaneously open connections
     that libcurl may cache.
     By default the size will be enlarged to fit four times the number
     of handles added via curl_multi_add_handle.
     When the cache is full, curl closes the oldest one in the cache
     to prevent the number of open connections from increasing.
     Available as of cURL 7.16.3.
Specifies the maximum number of concurrent streams for connections
     that cURL should support on connections using HTTP/2.
     Valid values range from 1
     to 2147483647 (2^31 - 1).
     The value passed here would be honored
     based on other system resources properties.
     Default is 100.
     Available as of PHP 8.2.0 and cURL 7.67.0.
Specifies the maximum number of connections to a single host.
     Available as of PHP 7.0.7 and cURL 7.30.0
Specifies the maximum number of requests in a pipeline.
     Available as of PHP 7.0.7 and cURL 7.30.0
Specifies the maximum number of simultaneously open connections.
     Available as of PHP 7.0.7 and cURL 7.30.0
Pass 1 to enable or 0 to disable. Enabling pipelining on a multi
     handle will make it attempt to perform HTTP Pipelining as far as
     possible for transfers using this handle. This means that adding
     a second request that can use an already existing connection will "pipe"
     the second request on the same connection.
     As of cURL 7.43.0, the value is a bitmask,
     and passing 2 will try to multiplex the new
     transfer over an existing HTTP/2 connection.
     Passing 3 instructs cURL to ask for pipelining and multiplexing
     independently of each other.
     As of cURL 7.62.0, setting the pipelining bit has no effect.
     Instead of integer literals, the CURLPIPE_* constants can also be used.
     Available as of cURL 7.16.0.
Pass a callable that will be registered to handle server
     pushes and should have the following signature:
     
      intpushfunction
      resourceparent_ch
      resourcepushed_ch
      arrayheaders
     
     
      
       parent_ch
       
        
         The parent cURL handle (the request the client made).
        
       
      
      
       pushed_ch
       
        
         A new cURL handle for the pushed request.
        
       
      
      
       headers
       
        
         The push promise headers.
        
       
      
     
     The push function is supposed to return either
     CURL_PUSH_OK if it can handle the push, or
     CURL_PUSH_DENY to reject it.
     Available as of PHP 7.1.0 and cURL 7.44.0
The parent cURL handle (the request the client made).
A new cURL handle for the pushed request.
The push promise headers.
Installing OCI8 from PECL Using the pecl Command
The OCI8 extension can be added to an existing PHP installation by using
  the PECL repository.
If you are behind a firewall, set PEAR's proxy, for example:
    
    
     
      

pear config-set http_proxy http://my-proxy.example.com:80/

      
     
    
   
   
    
     Run
    
    
     
      

pecl install oci8

      
     
    
    
     For PHP 7, use pecl install oci8-2.2.0
    
   
   
    
     When prompted, enter either the value of $ORACLE_HOME, or
     instantclient,/path/to/instant/client/lib.
    
    
      Note: Do not enter variable names like $ORACLE_HOME
      or $HOME because pecl will not
      expand them.  Instead, enter an expanded path, for
      example /opt/oracle/product/19c/dbhome_1
      or instantclient,/Users/myname/Downloads/instantclient_19_8
    
   
   
    
     If you get an error oci8_dtrace_gen.h: No such file or
     directory, it means PHP was built
     with DTrace Dynamic Tracing enabled.
     Install using:
    
   
    
     

$ export PHP_DTRACE=yes
$ pecl install oci8

     
    
       
      
   
    
      Edit your  file and add the line:
    
    
      
        
          
extension=oci8.so

        
      
    
    
      Make sure the 
      directive extension_dir is
      set to the directory that oci8.so was installed
      in.
If you are behind a firewall, set PEAR's proxy, for example:
pear config-set http_proxy http://my-proxy.example.com:80/
Run
pecl install oci8
For PHP 7, use pecl install oci8-2.2.0
When prompted, enter either the value of $ORACLE_HOME, or
     instantclient,/path/to/instant/client/lib.
Note: Do not enter variable names like $ORACLE_HOME
      or $HOME because pecl will not
      expand them.  Instead, enter an expanded path, for
      example /opt/oracle/product/19c/dbhome_1
      or instantclient,/Users/myname/Downloads/instantclient_19_8
If you get an error oci8_dtrace_gen.h: No such file or
     directory, it means PHP was built
     with DTrace Dynamic Tracing enabled.
     Install using:
$ export PHP_DTRACE=yes
$ pecl install oci8
Edit your  file and add the line:
extension=oci8.so
Make sure the 
      directive extension_dir is
      set to the directory that oci8.so was installed
      in.
Installing OCI8 from PECL Using phpize
To install OCI8 on an existing PHP installation when
  the pecl command is not available, manually download
  the PECL OCI8 package,
  e.g. oci8-3.0.0.tgz.
Extract the package:
    
    
     
      

tar -zxf oci8-3.0.0.tgz
cd oci8-3.0.0

      
     
    
   
   
    
     Prepare the package:
    
    
     
      

phpize

      
     
    
   
   
    
     Configure the package, either
     using $ORACLE_HOME or Instant Client
    
    
     
      

./configure -with-oci8=shared,$ORACLE_HOME

      
     
    
    
     or
    
    
     
      

./configure -with-oci8=shared,instantclient,/path/to/instant/client/lib

      
     
    
   
   
    
     Install the package:
    
    
     
      

make install

      
     
    
   
   
    
     If you get an error oci8_dtrace_gen.h: No such file or
     directory, it means PHP was built
     with DTrace Dynamic Tracing enabled.
     Re-run the configure and make
     commands after setting this environment variable:
    
    
     
      

$ export PHP_DTRACE=yes

     
    
       
   
   
    
      Edit your  file and add the line:
    
    
      
        
          
extension=oci8.so

        
      
    
    
      Make sure the 
      directive extension_dir is
      set to the directory that oci8.so was installed
      in.
Extract the package:
tar -zxf oci8-3.0.0.tgz
cd oci8-3.0.0
Prepare the package:
phpize
Configure the package, either
     using $ORACLE_HOME or Instant Client
./configure -with-oci8=shared,$ORACLE_HOME
or
./configure -with-oci8=shared,instantclient,/path/to/instant/client/lib
Install the package:
make install
If you get an error oci8_dtrace_gen.h: No such file or
     directory, it means PHP was built
     with DTrace Dynamic Tracing enabled.
     Re-run the configure and make
     commands after setting this environment variable:
$ export PHP_DTRACE=yes
Edit your  file and add the line:
extension=oci8.so
Make sure the 
      directive extension_dir is
      set to the directory that oci8.so was installed
      in.
Installing OCI8 as a Shared Extension when Building PHP
If you are building PHP from source code, the
  configuration shared option can be used to build OCI8 as a shared library
  that can be dynamically loaded into PHP.  Building a shared extension allows
  OCI8 to be upgraded easily without impacting the rest of PHP.
Configure OCI8 using one of the following configure options.
If using the free Oracle Instant
     Client libraries, then do:
    
    
     
      

./configure --with-oci8=shared,instantclient,/path/to/instant/client/lib

      
     
    
    
     If Instant Client 12.2 (or earlier) is installed from ZIP files, make sure to create
     the library symbolic link first, for example ln -s
     libclntsh.so.12.1 libclntsh.so.
    
    
     If using an RPM-based installation of Oracle Instant Client, the
     configure line will look like this:
    
    
     
      

./configure --with-oci8=shared,instantclient,/usr/lib/oracle/<version>/client/lib

      
     
    
    
     For example, --with-oci8=shared,instantclient,/usr/lib/oracle/19.9/client/lib
    
   
   
    
     If using an Oracle database or full Oracle Client installation then do:
    
    
     
      

./configure --with-oci8=shared,$ORACLE_HOME

      
     
    
    
     Make sure the web server user
     (nobody, www) has access to
     the libraries, initialization files
     and tnsnames.ora (if used) under
     the $ORACLE_HOME directory.  With Oracle
     10gR2, you may need to run
     the $ORACLE_HOME/install/changePerm.sh
     utility to give directory access.
If using the free Oracle Instant
     Client libraries, then do:
./configure --with-oci8=shared,instantclient,/path/to/instant/client/lib
If Instant Client 12.2 (or earlier) is installed from ZIP files, make sure to create
     the library symbolic link first, for example ln -s
     libclntsh.so.12.1 libclntsh.so.
If using an RPM-based installation of Oracle Instant Client, the
     configure line will look like this:
./configure --with-oci8=shared,instantclient,/usr/lib/oracle/<version>/client/lib
For example, --with-oci8=shared,instantclient,/usr/lib/oracle/19.9/client/lib
If using an Oracle database or full Oracle Client installation then do:
./configure --with-oci8=shared,$ORACLE_HOME
Make sure the web server user
     (nobody, www) has access to
     the libraries, initialization files
     and tnsnames.ora (if used) under
     the $ORACLE_HOME directory.  With Oracle
     10gR2, you may need to run
     the $ORACLE_HOME/install/changePerm.sh
     utility to give directory access.
After configuration, follow the usual PHP building procedure,
  e.g. make install.  The OCI8 shared extension
  oci8.so library will be created.  It may need
  to be manually moved to the PHP extension directory, specified by
  the extension_dir option in
  your  file.
To complete installation of OCI8, edit  and add the line:
extension=oci8.so
Installing OCI8 as a Statically Compiled Extension when Building PHP
If you are building PHP from source code, you can configure PHP to include
  OCI8 as a static extension using one of the following configure options.
If using Oracle Instant Client, then do:
    
    
     
      

./configure --with-oci8=instantclient,/path/to/instant/client/lib

      
     
    
   
   
    
     If using an Oracle database or full Oracle Client installation then do:
    
    
     
      

./configure --with-oci8=$ORACLE_HOME
If using Oracle Instant Client, then do:
./configure --with-oci8=instantclient,/path/to/instant/client/lib
If using an Oracle database or full Oracle Client installation then do:
./configure --with-oci8=$ORACLE_HOME
After configuration, follow the usual PHP building procedure,
  e.g. make install.  After successful
  compilation, you do not need to add oci8.so to
  .  No additional build steps are required.
Installing OCI8 on Windows
The OCI8 extension can be added to an existing PHP installation by using the
  DLLs from PECL repository or
  the libraries in your PHP installation's ext directory.
With Oracle 12c (or later) libraries, uncomment one of
  the  lines extension=php_oci8_12c.dll
  or extension=php_oci8_11g.dll
  or extension=php_oci8.dll. Only one of these DLLs may be
  enabled at a time. DLLs with higher versions may contain more
  functionality. Not all DLLs may be available for all versions of PHP.  Make
  sure extension_dir is set to the
  directory containing the PHP extension DLLs.
If using Instant Client, set the system PATH
  environment variable to the Oracle library directory.
Setting the Oracle Environment
Before using this extension, make sure that the Oracle environment
  variables are properly set for the web daemon user.  If your web
  server is automatically started at boot time then make sure that the
  boot-time environment is also configured correctly.
Do not set Oracle environment variables
   using putenv in a PHP script because Oracle
   libraries may be loaded and initialized before your script
   runs. Variables set with putenv may then cause
   conflicts, crashes, or unpredictable behavior.  Some functions may
   work but others might give subtle errors. The variables should be
   set up before the web server is started.
On Red Hat Linux and variants, export variables at the end of
  /etc/sysconfig/httpd.  Other systems with
  Apache 2 may use an envvars script in the
  Apache bin directory.  A third option, the
  Apache SetEnv directive
  in httpd.conf, may work in some systems but is
  known to be insufficient in others.
To check that environment variables are set correctly,
  use phpinfo and check
  the Environment (not the Apache
  Environment) section contains the expected variables.
The variables that might be needed are included in the following
  table.  Refer to the Oracle documentation for more information on
  all the available variables.
  
   Common Oracle Environment Variables
   
    
     
      Name
      Purpose
     
    
    
     
      ORACLE_HOME
      Contains the directory of the full Oracle Database
      software.  Do not set this when using Oracle Instant Client as
      it is unnecessary and may cause installation problems.
     
     
      ORACLE_SID
      Contains the name of the database on the local machine to
      be connected to. There is no need to set this if you using
      Oracle Instant Client, or always pass the connection parameter
      to oci_connect.
     
     
      LD_LIBRARY_PATH
      Set this (or its platform equivalent, such
      as LIBPATH, or SHLIB_PATH) to the
      location of the Oracle libraries, for
      example $ORACLE_HOME/lib
      or /usr/lib/oracle/18.5/client/lib. Note with Instant
      Client ZIP files on Linux it is more reliable to
      use ldconfig instead, see the Instant Client
      installation instructions.  With Instant Client 19 (or later) RPM
      files, ldconfig is automatically run for you.  Some
      users use
      LD_PRELOAD instead
      of LD_LIBRARY_PATH.
     
     
      NLS_LANG
      This is the primary variable for setting the character
      set and globalization information used by the Oracle
      libraries.
     
     
      ORA_SDTZ
      Sets the Oracle session timezone.
     
     
      TNS_ADMIN
      Contains the directory where the Oracle Net Services configuration
      files such as tnsnames.ora
      and sqlnet.ora are kept.  Not needed if
      the oci_connect connection string uses the Easy
      Connect naming syntax such as localhost/XE.  Not needed
      if the network configuration files are in one of the default locations
      such
      as /usr/lib/oracle/VERSION/client/lib/network/admin, $ORACLE_HOME/network/admin
      or /etc.
     
    
   
  
   Less frequently used Oracle environment variables include
   TWO_TASK, ORA_TZFILE, and the
   various Oracle globalization settings
   like NLS* and the ORA_NLS_*
   variables.
Common Oracle Environment Variables
Troubleshooting
The most common problem with installing OCI8 is not having the
  Oracle environment correctly set.  This typically appears as a
  problem using oci_connect
  or oci_pconnect.  The error may be a PHP error
  such as Call to undefined function
  oci_connect(), an Oracle error such as ORA-12705, or even
  an Apache crash.  Check the Apache log files for startup errors and
  see the sections above to resolve this problem.
While network errors like ORA-12154 or ORA-12514 indicate an Oracle
  network naming or configuration issue, the root cause may be because
  the PHP environment is incorrectly set up and Oracle libraries are
  unable to locate the tnsnames.ora configuration
  file.
On Windows, having multiple versions of Oracle on the one machine
  can easily cause library clashes unless care is taken to make sure
  PHP only uses the correct version of Oracle.
A utility to examine what libraries are being looked for and loaded
  can help resolve missing or clashing library issues, particularly on
  Windows.
If the web server doesn't start or crashes at
  startup
Check that Apache is linked with the pthread library:
# ldd /www/apache/bin/httpd
  libpthread.so.0 => /lib/libpthread.so.0 (0x4001c000)
  libm.so.6 => /lib/libm.so.6 (0x4002f000)
  libcrypt.so.1 => /lib/libcrypt.so.1 (0x4004c000)
  libdl.so.2 => /lib/libdl.so.2 (0x4007a000)
  libc.so.6 => /lib/libc.so.6 (0x4007e000)
  /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)
If the libpthread is not listed, then reinstall Apache:
# cd /usr/src/apache_1.3.xx
# make clean
# LIBS=-lpthread ./config.status
# make
# make install
Please note that on some systems like UnixWare, it is libthread
   instead of libpthread. PHP and Apache have to be configured with
   EXTRA_LIBS=-lthread.
Aliases and deprecated Mysqli
Many examples in this reference require an XML file. We will use 
  book.xml that contains the following:
book.xml
   

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" [
]>
<book id="listing">
 <title>My lists</title>
 <chapter id="books">
  <title>My books</title>
  <para>
   <informaltable>
    <tgroup cols="4">
     <thead>
      <row>
       <entry>Title</entry>
       <entry>Author</entry>
       <entry>Language</entry>
       <entry>ISBN</entry>
      </row>
     </thead>
     <tbody>
      <row>
       <entry>The Grapes of Wrath</entry>
       <entry>John Steinbeck</entry>
       <entry>en</entry>
       <entry>0140186409</entry>
      </row>
      <row>
       <entry>The Pearl</entry>
       <entry>John Steinbeck</entry>
       <entry>en</entry>
       <entry>014017737X</entry>
      </row>
      <row>
       <entry>Samarcande</entry>
       <entry>Amine Maalouf</entry>
       <entry>fr</entry>
       <entry>2253051209</entry>
      </row>
      <!-- TODO: I have a lot of remaining books to add.. -->
     </tbody>
    </tgroup>
   </informaltable>
  </para>
 </chapter>
</book>
book.xml
PCRE Patterns
Examples of valid patterns
   
    /\/\w+/
    |(\d{3})-\d+|Sm
    /^(?i)php[34]/
    {^\s+(\s+)?$}
Examples of valid patterns
/\/\w+/
|(\d{3})-\d+|Sm
/^(?i)php[34]/
{^\s+(\s+)?$}
Examples of invalid patterns
   
    
     
      /href='(.*)' - missing ending delimiter
     
    
    
     
      /\w+\s*\w+/J - unknown modifier 'J'
     
    
    
     
      1-\d3-\d3-\d4| - missing starting delimiter
Examples of invalid patterns
/href='(.*)' - missing ending delimiter
/\w+\s*\w+/J - unknown modifier 'J'
1-\d3-\d3-\d4| - missing starting delimiter
In this example, we first define a base class and an extension
  of the class. The base class describes a general vegetable,
  whether it is edible, and what is its color. The subclass
  Spinach adds a method to cook it and another to
  find out if it is cooked.
Class Definitions
   Vegetable
   

<?php

class Vegetable {
    public $edible;

    public $color;

    public function __construct($edible, $color = "green")
    {
        $this->edible = $edible;
        $this->color = $color;
    }

    public function isEdible()
    {
        return $this->edible;
    }

    public function getColor()
    {
        return $this->color;
    }
}

?>

   
   Spinach
   

<?php

class Spinach extends Vegetable {
    public $cooked = false;

    public function __construct()
    {
        parent::__construct(true, "green");
    }

    public function cook()
    {
        $this->cooked = true;
    }

    public function isCooked()
    {
        return $this->cooked;
    }
}

?>
Class Definitions
Vegetable
Spinach
We then instantiate 2 objects from these classes and print out
 information about them, including their class parentage.
 We also define some utility functions, mainly to have a nice printout
 of the variables.
test_script.php
   

<?php

// register autoloader to load classes
spl_autoload_register();

function printProperties($obj)
{
    foreach (get_object_vars($obj) as $prop => $val) {
        echo "\t$prop = $val\n";
    }
}

function printMethods($obj)
{
    $arr = get_class_methods(get_class($obj));
    foreach ($arr as $method) {
        echo "\tfunction $method()\n";
    }
}

function objectBelongsTo($obj, $class)
{
    if (is_subclass_of($obj, $class)) {
        echo "Object belongs to class " . get_class($obj);
        echo ", a subclass of $class\n";
    } else {
        echo "Object does not belong to a subclass of $class\n";
    }
}

// instantiate 2 objects
$veggie = new Vegetable(true, "blue");
$leafy = new Spinach();

// print out information about objects
echo "veggie: CLASS " . get_class($veggie) . "\n";
echo "leafy: CLASS " . get_class($leafy);
echo ", PARENT " . get_parent_class($leafy) . "\n";

// show veggie properties
echo "\nveggie: Properties\n";
printProperties($veggie);

// and leafy methods
echo "\nleafy: Methods\n";
printMethods($leafy);

echo "\nParentage:\n";
objectBelongsTo($leafy, Spinach::class);
objectBelongsTo($leafy, Vegetable::class);

?>

   
   
   

veggie: CLASS Vegetable
leafy: CLASS Spinach, PARENT Vegetable

veggie: Properties
        edible = 1
        color = blue

leafy: Methods
        function __construct()
        function cook()
        function isCooked()
        function isEdible()
        function getColor()

Parentage:
Object does not belong to a subclass of Spinach
Object belongs to class Spinach, a subclass of Vegetable

   
   
    One important thing to note in the example above is that
    the object $leafy is an instance of the class
    Spinach which is a subclass of
    Vegetable.
test_script.php
One important thing to note in the example above is that
    the object $leafy is an instance of the class
    Spinach which is a subclass of
    Vegetable.
mqseries
Supported Character Encodings
Currently the following character encodings are supported by the
  mbstring module. Any of those Character encodings
  can be specified in the encoding parameter of
  mbstring functions.
The following character encodings are supported in this PHP
  extension:
UCS-4*
UCS-4BE
UCS-4LE*
UCS-2
UCS-2BE
UCS-2LE
UTF-32*
UTF-32BE*
UTF-32LE*
UTF-16*
UTF-16BE*
UTF-16LE*
UTF-7
UTF7-IMAP
UTF-8*
ASCII*
EUC-JP*
SJIS*
eucJP-win*
SJIS-win*
ISO-2022-JP
ISO-2022-JP-MS
CP932
CP51932
SJIS-mac (alias: MacJapanese)
SJIS-Mobile#DOCOMO (alias: SJIS-DOCOMO)
SJIS-Mobile#KDDI (alias: SJIS-KDDI)
SJIS-Mobile#SOFTBANK (alias: SJIS-SOFTBANK)
UTF-8-Mobile#DOCOMO (alias: UTF-8-DOCOMO)
UTF-8-Mobile#KDDI-A
UTF-8-Mobile#KDDI-B (alias: UTF-8-KDDI)
UTF-8-Mobile#SOFTBANK (alias: UTF-8-SOFTBANK)
ISO-2022-JP-MOBILE#KDDI (alias: ISO-2022-JP-KDDI)
JIS
JIS-ms
CP50220
CP50220raw
CP50221
CP50222
ISO-8859-1*
ISO-8859-2*
ISO-8859-3*
ISO-8859-4*
ISO-8859-5*
ISO-8859-6*
ISO-8859-7*
ISO-8859-8*
ISO-8859-9*
ISO-8859-10*
ISO-8859-13*
ISO-8859-14*
ISO-8859-15*
ISO-8859-16*
byte2be
byte2le
byte4be
byte4le
BASE64
HTML-ENTITIES (alias: HTML)
7bit
8bit
EUC-CN*
CP936
GB18030
HZ
EUC-TW*
CP950
BIG-5*
EUC-KR*
UHC (alias: CP949)
ISO-2022-KR
Windows-1251 (alias: CP1251)
Windows-1252 (alias: CP1252)
CP866 (alias: IBM866)
KOI8-R*
KOI8-U*
ArmSCII-8 (alias: ArmSCII8)
* denotes encodings usable also in regular expressions.
Any  entry which accepts an encoding name
  can also use the values auto and
  pass.
  mbstring functions which accept an encoding
  name can also use the value auto.
If pass is set, no character
  encoding conversion is performed.
If auto is set, it is expanded to
  the list of encodings defined per the NLS.
  For instance, if the NLS is set to Japanese,
  the value is assumed to be
  ASCII,JIS,UTF-8,EUC-JP,SJIS.
See also mb_detect_order