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shm_has_var

(PHP 5 >= 5.3.0, PHP 7, PHP 8)

shm_has_var — Check whether a specific entry exists

Description

shm_has_var(SysvSharedMemory $shm, int $key): bool

Checks whether a specific key exists inside a shared memory segment.

Parameters

shm: A shared memory segment obtained from shm_attach().
key: The variable key.

Return Values

Returns true if the entry exists, otherwise false

Changelog

Version	Description
8.0.0	`shm` expects a SysvSharedMemory instance now; previously, a resource was expected.

See Also

shm_get_var() - Returns a variable from shared memory
shm_put_var() - Inserts or updates a variable in shared memory

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.shm-has-var.php