bionic (3) mq_setattr.3posix.gz

Provided by: manpages-posix-dev_2013a-2_all bug

PROLOG
       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
       mq_setattr — set message queue attributes (REALTIME)


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()  function  shall  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
       shall be set to the specified values upon successful completion of mq_setattr():

       mq_flags    The  value  of  this  member  is the bitwise-logical OR of zero or more of O_NONBLOCK and any
                   implementation-defined flags.

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

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


RETURN VALUE
       Upon  successful  completion, the function shall return a value of zero and the attributes of the message
       queue shall have been changed as specified.

       Otherwise, the message queue attributes shall be unchanged, and the function shall return a value  of  −1
       and set errno to indicate the error.


ERRORS
       The mq_setattr() 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(), msgctl(), msgget(), msgrcv(), msgsnd()

       The Base Definitions volume of POSIX.1‐2008, <mqueue.h>


       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 .