(PHP 3 >= 3.0.6, PHP 4, PHP 5)
sem_get -- Get a semaphore id
Description
resource
sem_get ( int key [, int max_acquire [, int perm [, int auto_release]]] )
sem_get() returns an id that can be used to
access the System V semaphore with the given key.
The semaphore is created if necessary using the permission bits specified in
perm (defaults to 0666). The number of processes that can
acquire the semaphore simultaneously is set to max_acquire
(defaults to 1). Actually this value is set only if the process
finds it is the only process currently attached to the semaphore.
Optional parameter auto_release specifies if the
semaphore should be automatically released on request shutdown.
It is available since PHP 4.3.0.
Returns a positive semaphore identifier on success, or FALSE on
error.
A second call to sem_get() for the same key
will return a different semaphore identifier, but both
identifiers access the same underlying semaphore.
See also sem_acquire(),
sem_release(), and ftok().