PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

SEM_CLOSE(3P)             POSIX Programmer's Manual            SEM_CLOSE(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       sem_close — close a named semaphore

SYNOPSIS         top

       #include <semaphore.h>

       int sem_close(sem_t *sem);

DESCRIPTION         top

       The sem_close() function shall indicate that the calling process is
       finished using the named semaphore indicated by sem.  The effects of
       calling sem_close() for an unnamed semaphore (one created by
       sem_init()) are undefined. The sem_close() function shall deallocate
       (that is, make available for reuse by a subsequent sem_open() by this
       process) any system resources allocated by the system for use by this
       process for this semaphore. The effect of subsequent use of the
       semaphore indicated by sem by this process is undefined. If the
       semaphore has not been removed with a successful call to
       sem_unlink(), then sem_close() has no effect on the state of the
       semaphore. If the sem_unlink() function has been successfully invoked
       for name after the most recent call to sem_open() with O_CREAT for
       this semaphore, then when all processes that have opened the
       semaphore close it, the semaphore is no longer accessible.

RETURN VALUE         top

       Upon successful completion, a value of zero shall be returned.
       Otherwise, a value of −1 shall be returned and errno set to indicate
       the error.

ERRORS         top

       The sem_close() function may fail if:

       EINVAL The sem argument is not a valid semaphore descriptor.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       None.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       semctl(3p), semget(3p), semop(3p), sem_init(3p), sem_open(3p),
       sem_unlink(3p)

       The Base Definitions volume of POSIX.1‐2008, semaphore.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) In the event of any discrepancy between this version and
       the original IEEE and The Open Group Standard, the original IEEE and
       The Open Group Standard is the referee document. The original
       Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                       SEM_CLOSE(3P)

Pages that refer to this page: semaphore.h(0p)_Exit(3p)semctl(3p)semget(3p)semop(3p)sem_open(3p)sem_unlink(3p)