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33 .Nd POSIX message queue file system
37 .Cd "options P1003_1B_MQUEUE"
39 To load as a kernel loadable module:
41 .Dl "kldload mqueuefs"
45 module will permit the
50 The module contains system calls to manipulate
53 It also contains a file system to implement a view for all message queues of
55 This helps users to keep track of their message queues and make
56 it more easily usable without having to invent additional tools.
58 The most common usage is as follows:
60 .Dl "mount -t mqueuefs null /mnt/mqueue"
66 It is possible to define an entry in
68 that looks similar to:
70 null /mnt/mqueue mqueuefs rw 0 0
77 mount point during system boot.
80 as a permanent mount point is not advised as its intention
81 has always been to be a temporary mount point.
84 for more information on
88 Some common tools can be used on the file system, e.g.:
95 To use only the message queue system calls, it is not necessary for
96 user to mount the file system, just load the module or compile it
98 Manually creating a file, for example,
99 .Dq Li "touch /mnt/mqueue/myqueue" ,
100 will create a message queue named
102 in the kernel, default
103 message queue attributes will be applied to the queue.
105 advised to use this method to create a queue;
106 it is better to use the
108 system call to create a queue as it
109 allows the user to specify different attributes.
111 To see the queue's attributes, just read the file:
113 .Dl "cat /mnt/mqueue/myqueue"
121 This manual page was written by
122 .An David Xu Aq Mt davidxu@FreeBSD.org .