mqueue.h(3head) [opensolaris man page]

mqueue.h(3HEAD) 						      Headers							   mqueue.h(3HEAD)

NAME

       mqueue.h, mqueue - message queues

SYNOPSIS

       #include <mqueue.h>

DESCRIPTION

       The  <mqueue.h>	header	defines  the  mqd_t type, which is used for message queue descriptors.	This will not be an array type.  A message
       queue descriptor may be implemented using a file descriptor, in which case applications can open up to at least OPEN_MAX file  and  message
       queues.

       The <mqueue.h> header defines the sigevent structure (as described in <signal.h>, see signal.h(3HEAD)) 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.	A  mq_attr
       structure has the following members:

	 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

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

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       fcntl.h(3HEAD), signal.h(3HEAD), time.h(3HEAD), types.h(3HEAD), attributes(5), standards(5)

SunOS 5.11							    30 Aug 2002 						   mqueue.h(3HEAD)

mq_getattr(3RT) 					    Realtime Library Functions						   mq_getattr(3RT)

NAME

       mq_getattr - get message queue attributes

SYNOPSIS

       cc [ flag... ] file... -lrt [ library... ]
       #include <mqueue.h>

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

DESCRIPTION

       The  mqdes argument specifies a message queue descriptor. The mq_getattr() function is used to get status information and attributes of the
       message queue and the open message queue description associated with the message queue descriptor. The results are returned in the  mq_attr
       structure referenced by the mqstat argument.

       Upon  return,  the  following members will 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(3RT) calls:

       mq_flags        message queue flags

       The following attributes of the message queue are returned as set at message queue creation:

       mq_maxmsg       maximum number of messages

       mq_msgsize      maximum message size

       mq_curmsgs      number of messages currently on the queue.

RETURN VALUES

       Upon successful completion, the mq_getattr() function returns 0. Otherwise, the function returns -1 and sets errno to indicate the error.

ERRORS

       The  mq_getattr() function will fail if:

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

       ENOSYS	       The mq_getattr() function is not supported by the system.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       msgctl(2), msgget(2), msgrcv(2), msgsnd(2), mqueue.h(3HEAD), mq_open(3RT), mq_send(3RT), mq_setattr(3RT), attributes(5), standards(5)

NOTES

       Solaris 2.6 was the first release to support the Asynchronous Input and Output option. Prior to this release, this function always returned
       -1 and set errno to ENOSYS.

SunOS 5.10							    28 Jun 2002 						   mq_getattr(3RT)