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NAME
       mq_getattr - get message queue attributes (REALTIME)


SYNOPSIS
       #include <mqueue.h>

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


DESCRIPTION
       The  mq_getattr()  function  shall  obtain status information and attributes of the message queue and the
       open message queue description associated with the message queue descriptor.

       The mqdes argument specifies a message queue descriptor.

       The results shall be returned in the mq_attr structure referenced by the mqstat argument.

       Upon return, the following members  shall  have  the  values  associated  with  the  open  message  queue
       description  as  set  when the message queue was opened and as modified by subsequent mq_setattr() calls:
       mq_flags.

       The following attributes of the message queue shall  be  returned  as  set  at  message  queue  creation:
       mq_maxmsg, mq_msgsize.

       Upon  return,  the following members within the mq_attr structure referenced by the mqstat argument shall
       be set to the current state of the message queue:

       mq_curmsgs
              The number of messages currently on the queue.


RETURN VALUE
       Upon successful completion, the mq_getattr() function shall return zero. Otherwise,  the  function  shall
       return -1 and set errno to indicate the error.


ERRORS
       The mq_getattr() function shall fail if:

       EBADF  The mqdes argument is not a valid message queue descriptor.

       The following sections are informative.


EXAMPLES
       None.


APPLICATION USAGE
       None.


RATIONALE
       None.


FUTURE DIRECTIONS
       None.


SEE ALSO
       mq_open()  ,  mq_send() , mq_setattr() , mq_timedsend() , msgctl() , msgget() , msgrcv() , msgsnd() , the
       Base Definitions volume of IEEE Std 1003.1-2001, <mqueue.h>


       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 .