Manual Pages  — MQUEUEFS

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This will mount mqueuefs at the /mnt/mqueue mount point during system boot. Using /mnt/mqueue as a permanent mount point is not advised as its intention has always been to be a temporary mount point. See hier(7) for more information on FreeBSD directory layout.

Some common tools can be used on the file system, e.g.: cat(1), chmod(1), chown(8), ls(1), rm(1), etc. To use only the message queue system calls, it is not necessary for user to mount the file system, just load the module or compile it into the kernel. Manually creating a file, for example, "touch /mnt/mqueue/myqueue", will create a message queue named myqueue in the kernel, default message queue attributes will be applied to the queue. It is not advised to use this method to create a queue; it is better to use the mq_open(2) system call to create a queue as it allows the user to specify different attributes.

To see the queue's attributes, just read the file:

    cat /mnt/mqueue/myqueue