How to limit max no of message in a posix message queue


 
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Old 06-10-2008
Lightbulb How to limit max no of message in a posix message queue

Hii can anyone pls tell how to limit the max no of message in a posix message queue. I have made changes in proc/sys/fs/mqueue/msg_max
But still whenever i try to read the value of max. message in the queue using attr.mq_curmsgs (where struct mq_attr attr) its giving the default value as 10.
can anyone help.
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mq_close(3C)						   Standard C Library Functions 					      mq_close(3C)

NAME
mq_close - close a message queue SYNOPSIS
#include <mqueue.h> int mq_close(mqd_t mqdes); DESCRIPTION
The mq_close() function removes the association between the message queue descriptor, mqdes, and its message queue. The results of using this message queue descriptor after successful return from this mq_close(), and until the return of this message queue descriptor from a subsequent mq_open(3C), are undefined. If the process (or thread) has successfully attached a notification request to the message queue via this mqdes, this attachment is removed and the message queue is available for another process to attach for notification. RETURN VALUES
Upon successful completion, mq_close() returns 0; otherwise, the function returns -1 and sets errno to indicate the error condition. ERRORS
The mq_close() function will fail if: EBADF The mqdes argument is an invalid message queue descriptor. ENOSYS The mq_open() function is not supported by the system. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ |ATTRIBUTE TYPE |ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Committed | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ |Standard |See standards(5). | +-----------------------------+-----------------------------+ SEE ALSO
mqueue.h(3HEAD), mq_notify(3C), mq_open(3C), mq_unlink(3C), 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 5.11 5 Feb 2008 mq_close(3C)

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