shm_attach

Function • Params and return types changed in PHP 8.0

Creates or open a shared memory segment.

PHP 5
PHP 7
PHP 8.0
Improved
PHP 8.1-8.2
PHP 8.3
PHP 8.4
PHP 8.5
PHP 8.6

shm_attach Function synopsis

shm_attach(
    int $key,
    ?int $size = null,
    int $permissions = 0666
  ): SysvSharedMemory|false

Parameters

$key

Typeint

A numeric shared memory segment ID

$size

OptionalType?intDefault valuenull

The memory size. If not provided, default to the sysvshm.init_mem in the php.ini, otherwise 10000 bytes.

$permissions

OptionalTypeintDefault value0666

The optional permission bits. Default to 0666.

Return value

TypeSysvSharedMemory|false

Returns a SysvSharedMemory instance on success, or false on failure.

Changes to the shm_attach Function

PHP 8.0

  • Return type added: SysvSharedMemory|false
  • Parameter type added for parameter #1 ($key): int
  • Parameter name of parameter #2 changed: $memsize to $size
  • Parameter type added for parameter #2 ($size): ?int
  • Parameter default value added for position #2 ($size): null
  • Parameter name of parameter #3 changed: $perm to $permissions
  • Parameter type added for parameter #3 ($permissions): int
  • Parameter default value added for position #3 ($permissions): 0666
  shm_attach(
-     $key,
+     int $key,
-     $memsize,
+     ?int $size = null,
-     $perm
+     int $permissions = 0666
-   )
+   ): SysvSharedMemory|false

shm_attach Function Availability

PHP VersionAvailability
PHP 8.6Future Release Yes
PHP 8.5Upcoming Release Yes
PHP 8.4Supported (Latest) Yes
PHP 8.3Supported Yes
PHP 8.2Security-Fixes Only Yes
PHP 8.1Security-Fixes Only Yes
PHP 8.0Unsupported Yes
PHP 7.4Unsupported Yes
PHP 7.3Unsupported Yes
PHP 7.2Unsupported Yes
PHP 7.1Unsupported Yes
PHP 7.0Unsupported Yes
PHP 5.6Unsupported Yes
PHP 5.5Unsupported Yes
PHP 5.4Unsupported Yes
PHP 5.3Unsupported Yes