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sem_unlink(3p) — Linux manual page

SEM_UNLINK(3P)          POSIX Programmer's ManualSEM_UNLINK(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_unlink — remove a named semaphore

SYNOPSIS        top

       #include <semaphore.h>       int sem_unlink(const char *name);

DESCRIPTION        top

       Thesem_unlink() function shall remove the semaphore named by the       stringname.  If the semaphore named byname is currently       referenced by other processes, thensem_unlink() shall have no       effect on the state of the semaphore. If one or more processes       have the semaphore open whensem_unlink() is called, destruction       of the semaphore is postponed until all references to the       semaphore have been destroyed by calls tosem_close(),_exit(), orexec.  Calls tosem_open() to recreate or reconnect to the       semaphore refer to a new semaphore aftersem_unlink() is called.       Thesem_unlink() call shall not block until all references have       been destroyed; it shall return immediately.

RETURN VALUE        top

       Upon successful completion, thesem_unlink() function shall return       a value of 0. Otherwise, the semaphore shall not be changed and       the function shall return a value of -1 and seterrno to indicate       the error.

ERRORS        top

       Thesem_unlink() function shall fail if:EACCESPermission is denied to unlink the named semaphore.ENOENTThe named semaphore does not exist.       Thesem_unlink() function may fail if:ENAMETOOLONG              The length of thename argument exceeds {_POSIX_PATH_MAX}              on systems that do not support the XSI option or exceeds              {_XOPEN_PATH_MAX} on XSI systems, or has a pathname              component that is longer than {_POSIX_NAME_MAX} on systems              that do not support the XSI option or longer than              {_XOPEN_NAME_MAX} on XSI systems.  A call tosem_unlink()              with aname argument that contains the same semaphore name              as was previously used in a successfulsem_open() call              shall not give an[ENAMETOOLONG]error.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       None.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       A future version might require thesem_open() andsem_unlink()       functions to have semantics similar to normal file system       operations.

SEE ALSO        top

semctl(3p),semget(3p),semop(3p),sem_close(3p),sem_open(3p)       The Base Definitions volume of POSIX.1‐2017,semaphore.h(0p)

COPYRIGHT        top

       Portions of this text are reprinted and reproduced in electronic       form from IEEE Std 1003.1-2017, Standard for Information       Technology -- Portable Operating System Interface (POSIX), The       Open Group Base Specifications Issue 7, 2018 Edition, Copyright       (C) 2018 by the Institute of Electrical and Electronics Engineers,       Inc and The Open Group.  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 athttp://www.opengroup.org/unix/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, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017SEM_UNLINK(3P)

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

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