sem_get

sem_get

(PHP 4, PHP 5)

sem_getGet a semaphore id

说明

resource sem_get ( int $key [, int $max_acquire = 1 [, int $perm = 0666 [, int $auto_release = 1 ]]] )

sem_get() returns an id that can be used to access the System V semaphore with the given key.

A second call to sem_get() for the same key will return a different semaphore identifier, but both identifiers access the same underlying semaphore.

参数

key

max_acquire

The number of processes that can acquire the semaphore simultaneously is set to max_acquire.

perm

The semaphore permissions. Actually this value is set only if the process finds it is the only process currently attached to the semaphore.

auto_release

Specifies if the semaphore should be automatically released on request shutdown.

返回值

Returns a positive semaphore identifier on success, or FALSE on error.

更新日志

版本 说明
4.3.0 The auto_release parameter was added.

参见


  • ftok
  • msg_get_queue
  • msg_queue_exists
  • msg_receive
  • msg_remove_queue
  • msg_send
  • msg_set_queue
  • msg_stat_queue
  • sem_acquire
  • sem_get
  • sem_release
  • sem_remove
  • shm_attach
  • shm_detach
  • shm_get_var
  • shm_has_var
  • shm_put_var
  • shm_remove
  • shm_remove_var
  • PHP MySQL HTML CSS JavaScript MSSQL AJAX .NET JSP Linux Mac ASP 服务器 SQL jQuery C# C++ java Android IOS oracle MongoDB SQLite wamp 交通频道