freebsd-src/lib/libc/sys/mq_close.2

.\" 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, 2003 Edition, Standard for Information
.\"   Technology -- Portable Operating System Interface (POSIX), The Open
.\"   Group Base Specifications Issue 6, Copyright (C) 2001-2003 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 .
.\"
.\" $FreeBSD$
.\"
.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, 2003 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 6, Copyright (C) 2001-2003 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 .