sem_remove

(PHP 4 >= 4.1.0, PHP 5, PHP 7)

sem_removeУдаление семафора

Описание

sem_remove ( resource $sem_identifier ) : bool

sem_remove() удаляет указанный семафор.

После удаления семафора он становится недоступным.

Список параметров

sem_identifier

Идентификатор семафора, возвращённый sem_get().

Возвращаемые значения

Возвращает TRUE в случае успешного завершения или FALSE в случае возникновения ошибки.

Смотрите также

  • sem_get() - Получение идентификатора семафора
  • sem_release() - Освобождение семафора
  • sem_acquire() - Захват семафора

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donotcallme at iwillcallyou dot com
5 years ago
sem_remove() shouldn't be part of a normal cleanup/teardown and should be called very rarely due to bugs in the implementation.

It doesn't seem to hurt to leave semaphores lying around and is likely to be more performance-friendly to do so.  If you are concerned about having too many semaphores floating around for an application (e.g. a file cache that uses ftok()), you can use some modulus arithmetic and simple addition to create a limited range of values for your semaphores off in the middle of nowhere.  For example, ftok() % 101 + 0xBADBEEF.  Be sure to replace 0xBADBEEF with your own random value.  The example limits the range to 101 semaphores.  101 is a prime number - so if you want more or less, be sure to replace it with a prime number since primes theoretically help distribute values more evenly.
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