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mq_close(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | STANDARDS | HISTORY | NOTES | SEE ALSO | COLOPHON 

mq_close(3)              Library Functions Manual             mq_close(3)

NAME         top

       mq_close - close a message queue descriptor

LIBRARY         top

       Real-time library (librt, -lrt)

SYNOPSIS         top

       #include <mqueue.h>

       int mq_close(mqd_t mqdes);

DESCRIPTION         top

       mq_close() closes the message queue descriptor mqdes.

       If the calling process has attached a notification request (see
       mq_notify(3)) to this message queue via mqdes, then this request
       is removed, and another process can now attach a notification
       request.

RETURN VALUE         top

       On success mq_close() returns 0; on error, -1 is returned, with
       errno set to indicate the error.

ERRORS         top

       EBADF  The message queue descriptor specified in mqdes is invalid.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
       โ”‚ Interface                            โ”‚ Attribute     โ”‚ Value   โ”‚
       โ”œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ค
       โ”‚ mq_close()                           โ”‚ Thread safety โ”‚ MT-Safe โ”‚
       โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       POSIX.1-2001.

NOTES         top

       All open message queues are automatically closed on process
       termination, or upon execve(2).

SEE ALSO         top

       mq_getattr(3), mq_notify(3), mq_open(3), mq_receive(3),
       mq_send(3), mq_unlink(3), mq_overview(7)

COLOPHON         top

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Linux man-pages 6.18            2026-02-08                    mq_close(3)

Pages that refer to this page: mq_getattr(3),  mq_notify(3),  mq_open(3),  mq_receive(3),  mq_send(3),  mq_unlink(3),  mq_overview(7)

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