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(3)						     Library Functions Manual						       mq_close(3)

NAME
mq_close - Closes a message queue (P1003.1b) LIBRARY
Realtime Library (librt.so, librt.a) SYNOPSIS
#include <mqueue.h> int mq_close ( mqd_t mqdes); PARAMETERS
mqdes Specifies a message queue descriptor. DESCRIPTION
The mq_close function closes a message queue. This function removes the association between the message queue descriptor, mqdes, and its open message queue description. When all message queue descriptors associated with an open message queue description have been closed, the associated open message queue description is removed. The message associated with the message queue will then be deleted if mq_unlink was already called, or is called after all processes have closed the queue. RETURN VALUES
On successful completion, the function returns the value 0 (zero); otherwise, the function returns the value -1 and sets errno to indicate the error. ERRORS
The mq_close function fails under the following conditions: [EBADF] The mqdes argument is an invalid message queue descriptor. [EFAULT] An internal virtual memory error occurred. RELATED INFORMATION
Functions: mq_open(3), mq_unlink(3) Guide to Realtime Programming delim off mq_close(3)