PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

MQ_GETATTR(3P)            POSIX Programmer's Manual           MQ_GETATTR(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       mq_getattr — get message queue attributes (REALTIME)

SYNOPSIS         top

       #include <mqueue.h>

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

DESCRIPTION         top

       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         top

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

ERRORS         top

       The mq_getattr() function may fail if:

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

       The following sections are informative.

EXAMPLES         top

       See mq_notify(3p).

APPLICATION USAGE         top

       None.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       mq_notify(3p), mq_open(3p), mq_send(3p), mq_setattr(3p), msgctl(3p),
       msgget(3p), msgrcv(3p), msgsnd(3p)

       The Base Definitions volume of POSIX.1‐2008, mqueue.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) 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.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                      MQ_GETATTR(3P)

Pages that refer to this page: mqueue.h(0p)mq_open(3p)msgctl(3p)msgget(3p)msgrcv(3p)msgsnd(3p)