Hi all,

I have developed a C++ application on Fedora 14. I have used POSIX message queues for IPC. I need multiple message queues (more than 100). I create a message queue using mq_open() as below:

MessageQueue = mq_open("/AppMessageQueue", O_RDWR | O_CREAT, 0666, NULL);

I need to run the application from a non-root user. From a non-root user, the application can create only up to 9 message queues. If the application tries to create 10th message queue, the error ENOMEM is generated.

Value in /proc/sys/fs/mqueue/msg_max is 10. Value in /proc/sys/fs/mqueue/msgsize_max is 8192. Value in /proc/sys/fs/mqueue/queues_max is 256.

From root user, the application can create more than 9 queues.

Why the application cannot create more than 9 queues from non-root user?

Any help is highly appreciated. Thank you in advance.