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sem_close(3)
NAME
  sem_close - Deallocates the specified named semaphore (P1003.1b)

SYNOPSIS
  #include <semaphore.h>

  int sem_close (
  sem_t *sem) ;

LIBRARY
  Realtime Library (librt.so, librt.a)

PARAMETERS
  sem References the semaphore to be closed.  Use the sem argument returned
      by the previous call to sem_open.

DESCRIPTION
  The sem_close function makes a semaphore available for reuse by
  deallocating any system resources allocated for use by the current process
  for the named semaphore indicated by sem.

  If the semaphore has not been removed with a call to sem_unlink, sem_close
  does not change the current state of the semaphore.

  If the semaphore has been removed with a call to sem_unlink after the most
  recent call to sem_open with O_CREAT, the semaphore is no longer available
  after all processes that opened the semaphore close it.

RETURN VALUES
  On a successful call, a value of 0 (zero) is returned. Otherwise, a value
  of -1 is returned and errno is set to indicate that an error occurred.

ERRORS
  The sem_close function fails under the following condition:

  [EINVAL]
      The sem argument is not a valid semaphore descriptor.

SEE ALSO
  Functions: sem_init(3), sem_open(3), sem_unlink(3)

  Guide to Realtime Programming

Index for Section 3

Alphabetical listing for S

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