mqueue.h

<mqueue.h>(P)							<mqueue.h>(P)



NAME
       mqueue.h - message queues (REALTIME)

SYNOPSIS
       #include <mqueue.h>

DESCRIPTION
       The  <mqueue.h>	header shall define the mqd_t type, which is used for
       message queue descriptors. This is not an array type.

       The  <mqueue.h>	header	shall  define  the  sigevent  structure	  (as
       described  in <signal.h> ) and the mq_attr structure, which is used in
       getting and setting the attributes of a message queue. Attributes  are
       initially  set when the message queue is created. An mq_attr structure
       shall have at least the following fields:


	      long    mq_flags	  Message queue flags.
	      long    mq_maxmsg	  Maximum number of messages.
	      long    mq_msgsize  Maximum message size.
	      long    mq_curmsgs  Number of messages currently queued.

       The following shall be declared as functions and may also  be  defined
       as macros. Function prototypes shall be provided.


	      int      mq_close(mqd_t);
	      int      mq_getattr(mqd_t, struct mq_attr *);
	      int      mq_notify(mqd_t, const struct sigevent *);
	      mqd_t    mq_open(const char *, int, ...);
	      ssize_t  mq_receive(mqd_t, char *, size_t, unsigned *);
	      int      mq_send(mqd_t, const char *, size_t, unsigned );
	      int      mq_setattr(mqd_t, const struct mq_attr *restrict,
			   struct mq_attr *restrict);

	      ssize_t  mq_timedreceive(mqd_t, char *restrict, size_t,
			   unsigned *restrict, const struct timespec *restrict);
	      int      mq_timedsend(mqd_t, const char *, size_t, unsigned ,
			   const struct timespec *);

	      int      mq_unlink(const char *);

       Inclusion of the <mqueue.h> header may make visible symbols defined in
       the headers <fcntl.h>, <signal.h>, <sys/types.h>, and <time.h>.

       The following sections are informative.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       <fcntl.h> , <signal.h> , <sys/types.h> , <time.h> , the System  Inter-
       faces   volume	of  IEEE Std 1003.1-2001,  mq_close(),	mq_getattr(),
       mq_notify(),   mq_open(),   mq_receive(),   mq_send(),	mq_setattr(),
       mq_timedreceive(), mq_timedsend(), mq_unlink()

COPYRIGHT
       Portions	 of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information  Technol-
       ogy  --	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 .



POSIX				     2003			<mqueue.h>(P)