04-27-2006
Check
this out. I do not know how valid the information is, but it seems to be quite good. From the info, it looks like you can have a default of 16384 bytes in a message queue at one time, and a default of 50 message queues on the system at one time.
The max bytes present on a message queue can be 65535 and the increase in max number of message queues is memory dependent.
Oh and one more thing, please remove the email address from your post. Against forum rules.
Last edited by blowtorch; 04-27-2006 at 05:50 AM..
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LEARN ABOUT OPENSOLARIS
mqueue
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)