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.
mq_close — close a message queue (REALTIME)
int mq_close(mqd_t mqdes);
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
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.
The mq_close() function shall fail if:
- The mqdes argument is not a valid message queue descriptor.
The following sections are informative.
mq_open(), mq_unlink(), msgctl(),
msgget(), msgrcv(), msgsnd()
The Base Definitions volume of POSIX.1‐2017,
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 .
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