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  • sem_remove()

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

    Remove a semaphore

    说明

    sem_remove(resource $sem_identifier): bool

    sem_remove() removes the given semaphore.

    After removing the semaphore, it is no longer accessible.

    参数

    $sem_identifier

    A semaphore resource identifier as returned by sem_get().

    返回值

    成功时返回TRUE,或者在失败时返回FALSE

    参见

    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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