= 5.3.0, PHP 7, PHP 8)shm_has_var — Check whether a specific entry exists說明shm_has_var(SysvSharedMemory $shm, int $key): boolChecks">
(PHP 5 >= 5.3.0, PHP 7, PHP 8)
shm_has_var — Check whether a specific entry exists
Checks whether a specific key exists inside a shared memory segment.
Returns true
if the entry exists, otherwise false