sem_close(2)							System Calls Manual						      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 refer-
       enced 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 sema-
       phore.

       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.
       Subsequent 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)