.\" Copyright (c) 2005 David Xu <davidxu@FreeBSD.org>
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.\" Portions of this text are reprinted and reproduced in electronic form
.\" from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology --
.\" Portable Operating System Interface (POSIX), The Open Group Base
.\" Specifications Issue 6, Copyright (C) 2001-2004 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.
.\"
.\" $FreeBSD: releng/12.2/lib/libc/sys/mq_close.2 208914 2010-06-08 16:48:59Z uqs $
.\"
.Dd November 29, 2005
.Dt MQ_CLOSE 2
.Os
.Sh NAME
.Nm mq_close
.Nd "close a message queue (REALTIME)"
.Sh LIBRARY
.Lb librt
.Sh SYNOPSIS
.In mqueue.h
.Ft int
.Fn mq_close "mqd_t mqdes"
.Sh DESCRIPTION
The
.Fn mq_close
system call removes the association between the message queue descriptor,
.Fa mqdes ,
and its message queue.
The results of using this message queue descriptor
after successful return from this
.Fn mq_close ,
and until the return of this message queue descriptor from a subsequent
.Fn mq_open ,
are undefined.
.Pp
If the process has successfully attached a notification request to the
message queue via this
.Fa mqdes ,
this attachment will be removed, and the message queue is available for
another process to attach for notification.
.Sh RETURN VALUES
.Rv -std
.Sh ERRORS
The
.Fn mq_close
system call
will fail if:
.Bl -tag -width Er
.It Bq Er EBADF
The
.Fa mqdes
argument is not a valid message queue descriptor.
.El
.Sh SEE ALSO
.Xr mq_open 2 ,
.Xr mq_unlink 2
.Sh STANDARDS
The
.Fn mq_close
system call conforms to
.St -p1003.1-2004 .
.Sh HISTORY
Support for
.Tn POSIX
message queues first appeared in
.Fx 7.0 .
.Sh COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology --
Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2004 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.