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sem_close(2)							  sem_close(2)

NAME
       sem_close - close a named POSIX semaphore

SYNOPSIS
DESCRIPTION
       is  used	 to close a named semaphore.  A successful call to will do the
       following: Remove the process's descriptor for the semaphore referenced
       by the specified structure sem.	Remove the semaphore referenced by the
       specified structure sem, if the semaphore is marked for	removal	 by  a
       call to and there are no other descriptors referencing this semaphore.

       When  the  process's  descriptor for the semaphore referenced by sem is
       removed, subsequent use of this semaphore by this  process  will	 fail.
       Descriptors for named semaphores are also removed by processes on exit.
       Calling does not affect other processes referencing the same semaphore.

       To use this function, link in the realtime library by specifying on the
       compiler or linker command line.

EXAMPLES
       The  following  call to will close a named semaphore referred to by sem
       by removing the process's descriptor to the semaphore and removing  the
       semaphore  if  it  is marked for removal by a previous and there are no
       descriptors referencing it.

RETURN VALUE
       If the semaphore was closed and the  descriptors	 referencing  it  were
       removed, returns 0 to the caller.

       If  the	semaphore could not be closed, the call returns -1 and sets to
       indicate the error.

ERRORS
       fails and does not perform the requested	 operation  if	the  following
       condition is encountered:

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

WARNINGS
       A single call will make the semaphore unusable by the process no matter
       how many times that process had called for the same semaphore.	Subse‐
       quent  calls  to by the same process for the same semaphore will result
       in an undefined behavior.

SEE ALSO
       sem_init(2), sem_open(2), sem_unlink(2), <semaphore.h>.

STANDARDS CONFORMANCE
								  sem_close(2)

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