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mq_getattr(3c)							mq_getattr(3c)

NAME
     mq_getattr - get attributes of a message queue

C SYNOPSIS
     #include <mqueue.h>

     int mq_getattr (mqd_t mqd, struct mq_attr *mqstat);

DESCRIPTION
     mq_getattr saves the attributes and status information of the message
     queue named by mqd into the mq_attr structure at address mqstat.  The
     following fields of the mq_attr structure are updated after a successful
     call to mq_getattr:

	long mq_flags;	      /* message queue flags */
	long mq_maxmsg;	      /* maximum number of messages */
	long mq_msgsize;      /* maximum size of a message*/
	long mq_curmsgs;      /* number of messages currently on queue */

     The fields have the following meanings:

     mq_flags  The set of flags which may be applied to the message queue on a
	       queue descriptor mqd basis, rather than to the queue itself.
	       The following flags are supported:

	       O_NONBLOCK If set, mq_send and mq_receive operations on the
	       queue named by mqd will not block when the queue is full or
	       empty, respectively.

     mq_maxmsg The maximum number of messages that can be queued at any one
	       time.  mq_send will fail, if O_NONBLOCK flag is set, or block
	       after this many messages are queued. This attribute of the
	       queue can be set only at time of queue creation.

     mq_msgsize
	       The maximum size of a message that can be sent to or received
	       from the queue.	This attribute of the queue can be set only at
	       the time of queue creation.

     mq_curmsgs
	       The number of messages currently on the message queue. This
	       attribute can only be queried and cannot be explicitly set.

     mq_getattr will fail if one or more of the following conditions are true:

     [EBADF]	    The message queue descriptor, mqd, is not valid.

     [EINTR]	    A signal interrupted the mq_getattr function call.

									Page 1

mq_getattr(3c)							mq_getattr(3c)

SEE ALSO
     mq_open(3c), intro(3c), mq_unlink(3c), mq_receive(3c), mq_send(3c),
     mq_setattr(3c), mq_notify(3c)

DIAGNOSTICS
     Upon successful completion, a value of 0 is returned and the attributes
     of the queue are written into the mq_attr structure pointed to by mqstat.
     Otherwise, a value of -1 is returned and errno is set to indicate the
     error.

									Page 2

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