xref: /illumos-gate/usr/src/man/man3c/mq_setattr.3c (revision bbf21555)

Sun Microsystems, Inc. gratefully acknowledges The Open Group for
permission to reproduce portions of its copyrighted documentation.
Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.

The Institute of Electrical and Electronics Engineers and The Open
Group, have given us permission to reprint portions of their
documentation.

In the following statement, the phrase ``this text'' refers to portions
of the system documentation.

Portions of this text are reprinted and reproduced in electronic form
in the SunOS Reference Manual, 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 these versions 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.

This notice shall appear on any product containing this material.

The contents of this file are subject to the terms of the
Common Development and Distribution License (the "License").
You may not use this file except in compliance with the License.

You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
or http://www.opensolaris.org/os/licensing.
See the License for the specific language governing permissions
and limitations under the License.

When distributing Covered Code, include this CDDL HEADER in each
file and include the License file at usr/src/OPENSOLARIS.LICENSE.
If applicable, add the following below this CDDL HEADER, with the
fields enclosed by brackets "[]" replaced with your own identifying
information: Portions Copyright [yyyy] [name of copyright owner]


Copyright 1989 AT&T
Portions Copyright (c) 1992, X/Open Company Limited All Rights Reserved
Copyright (c) 2008, Sun Microsystems, Inc. All Rights Reserved

MQ_SETATTR 3C "Feb 5, 2008"
NAME
mq_setattr - set/get message queue attributes
SYNOPSIS

#include <mqueue.h>

int mq_setattr(mqd_t mqdes, const struct mq_attr *mqstat,
 struct mq_attr *omqstat);
DESCRIPTION

The mq_setattr() function is used to set attributes associated with the open message queue description referenced by the message queue descriptor specified by mqdes.

The message queue attributes corresponding to the following members defined in the mq_attr structure are set to the specified values upon successful completion of mq_setattr(): mq_flags

The value of this member is either 0 or O_NONBLOCK.

The values of mq_maxmsg, mq_msgsize, and mq_curmsgs are ignored by mq_setattr().

If omqstat is non-NULL, mq_setattr() stores, in the location referenced by omqstat, the previous message queue attributes and the current queue status. These values are the same as would be returned by a call to mq_getattr() at that point.

RETURN VALUES

Upon successful completion, mq_setattr() returns 0 and the attributes of the message queue will have been changed as specified. Otherwise, the message queue attributes are unchanged, and the function returns -1 and sets errno to indicate the error.

ERRORS

The mq_setattr() function will fail if: EBADF

The mqdes argument is not a valid message queue descriptor.

ENOSYS

The mq_setattr() function is not supported by the system.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Committed
MT-Level MT-Safe
Standard See standards(7).
SEE ALSO

msgctl (2), msgget (2), msgrcv (2), msgsnd (2), mq_getattr (3C), mq_open (3C), mq_receive (3C), mq_send (3C), mqueue.h (3HEAD), attributes (7), standards (7)

NOTES

Solaris 2.6 was the first release to support the Asynchronous Input and Output option. Prior to this release, this function always returned -1 and set errno to ENOSYS.