MQ_UNLINK(3)               POSIX Programmer's Manual              MQ_UNLINK(3)



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

NAME
       mq_unlink -- remove a message queue (REALTIME)

SYNOPSIS
       #include <mqueue.h>

       int mq_unlink(const char *name);

DESCRIPTION
       The mq__unlink() function shall remove the message queue named by the
       string name.  If one or more processes have the message queue open when
       mq__unlink() is called, destruction of the message queue shall be
       postponed until all references to the message queue have been closed.
       However, the mq__unlink() call need not block until all references have
       been closed; it may return immediately.

       After a successful call to mq__unlink(), reuse of the name shall
       subsequently cause mq__open() to behave as if no message queue of this
       name exists (that is, mq__open() will fail if O_CREAT is not set, or
       will create a new message queue if O_CREAT is set).

RETURN VALUE
       Upon successful completion, the function shall return a value of zero.
       Otherwise, the named message queue shall be unchanged by this function
       call, and the function shall return a value of -1 and set errno to
       indicate the error.

ERRORS
       The mq__unlink() function shall fail if:

       EACCES Permission is denied to unlink the named message queue.

       EINTR  The call to mq__unlink() blocked waiting for all references to
              the named message queue to be closed and a signal interrupted
              the call.

       ENOENT The named message queue does not exist.

       The mq__unlink() function may fail if:

       ENAMETOOLONG
              The length of the name 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 to mq__unlink() with a name argument that
              contains the same message queue name as was previously used in a
              successful mq__open() call shall not give an [ENAMETOOLONG]
              error.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       A future version might require the mq__open() and mq__unlink() functions
       to have semantics similar to normal file system operations.

SEE ALSO
       mq__close(), mq__open(), msgctl(), msgget(), msgrcv(), msgsnd()

       The Base Definitions volume of POSIX.1-2017, <mqueue.h>

COPYRIGHT
       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 at http://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, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017                         MQ_UNLINK(3)
