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MQ_SETATTR(2)		  FreeBSD System Calls Manual		 MQ_SETATTR(2)

NAME
     mq_setattr	-- set message queue attributes	(REALTIME)

LIBRARY
     POSIX Real-time Library (librt, -lrt)

SYNOPSIS
     #include <mqueue.h>

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

DESCRIPTION
     The mq_setattr() system call sets 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	will be	set to the
     specified values upon successful completion of mq_setattr():

     mq_flags  The value of this member	is zero	or O_NONBLOCK.

     The values	of the mq_maxmsg, mq_msgsize, and mq_curmsgs members of	the
     mq_attr structure are ignored by mq_setattr().

RETURN VALUES
     Upon successful completion, the function returns a	value of zero and the
     attributes	of the message queue will have been changed as specified.

     Otherwise,	the message queue attributes are unchanged, and	the function
     returns a value of	-1 and sets the	global variable	errno to indicate the
     error.

ERRORS
     The mq_setattr() system call will fail if:

     [EBADF]		The mqdes argument is not a valid message queue	de-
			scriptor.

SEE ALSO
     mq_open(2), mq_send(2), mq_timedsend(2)

STANDARDS
     The mq_setattr() system call conforms to IEEE Std 1003.1-2004
     ("POSIX.1").

HISTORY
     Support for POSIX message queues first appeared in	FreeBSD	7.0.

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 Spec-
     ifications	Issue 6, Copyright (C) 2001-2004 by the	Institute of Electri-
     cal 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 ref-
     eree document.  The original Standard can be obtained online at
     http://www.opengroup.org/unix/online.html.

FreeBSD	13.0			 May 17, 2011			  FreeBSD 13.0

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | STANDARDS | HISTORY | COPYRIGHT

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