Section: POSIX Programmer's Manual (3P)
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.
--- close a message queue
int mq_close(mqd_t mqdes);
function shall remove the association between the message queue
and its message queue. The results of using this message queue
descriptor after successful return from this
and until the return of this message queue descriptor from a subsequent
If the process has successfully attached a notification request to the
message queue via this
this attachment shall be removed, and the message queue is available
for another process to attach for notification.
Upon successful completion, the
function shall return a value of zero; otherwise, the function shall
return a value of -1 and set
to indicate the error.
function shall fail if:
argument is not a valid message queue descriptor.
The following sections are informative.
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
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