This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface

       None.

       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_CLOSE(3POSIX)

       The mq_close() function shall remove the association between the message queue descriptor, mqdes, and its
       message  queue.  The  results  of  using  this message queue descriptor after successful return from this
       mq_close(), and until the return of this message  queue  descriptor  from  a  subsequent  mq_open(),  are
       undefined.

       If the process has successfully attached a notification request to the message queue via this mqdes, this
       attachment  shall  be  removed,  and  the  message  queue  is available for another process to attach for
       notification.

       The mq_close() function shall fail if:

       EBADF  The mqdes argument is not a valid message queue descriptor.

       Thefollowingsectionsareinformative.

       None.

       None.

       mq_close — close a message queue (REALTIME)

       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.

       None.

       Upon successful completion, the mq_close() function shall return a value of zero; otherwise, the function
       shall return a value of -1 and set errno to indicate the error.

mq_open(), mq_unlink(), msgctl(), msgget(), msgrcv(), msgsnd()

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

       #include <mqueue.h>

       int mq_close(mqd_t mqdes);