125 lines
3.5 KiB
Groff
125 lines
3.5 KiB
Groff
.\" Copyright (c) 2005 David Xu <davidxu@FreeBSD.org>
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice(s), this list of conditions and the following disclaimer as
|
|
.\" the first lines of this file unmodified other than the possible
|
|
.\" addition of one or more copyright notices.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice(s), this list of conditions and the following disclaimer in
|
|
.\" the documentation and/or other materials provided with the
|
|
.\" distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
|
|
.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
|
|
.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
|
|
.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
|
.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
|
|
.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
|
|
.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd November 30, 2005
|
|
.Dt MQUEUEFS 5
|
|
.Os
|
|
.Sh NAME
|
|
.Nm mqueuefs
|
|
.Nd POSIX message queue file system
|
|
.Sh SYNOPSIS
|
|
To link into kernel:
|
|
.Pp
|
|
.D1 Cd "options P1003_1B_MQUEUE"
|
|
.Pp
|
|
To load as a kernel loadable module:
|
|
.Pp
|
|
.Dl "kldload mqueuefs"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
module will permit the
|
|
.Fx
|
|
kernel to support
|
|
.Tn POSIX
|
|
message queue.
|
|
The module contains system calls to manipulate
|
|
.Tn POSIX
|
|
message queues.
|
|
It also contains a file system to implement a view for all message queues of
|
|
the system.
|
|
This helps users to keep track of their message queues and make
|
|
it more easily usable without having to invent additional tools.
|
|
.Pp
|
|
The most common usage is as follows:
|
|
.Pp
|
|
.Dl "mount -t mqueuefs null /mnt/mqueue"
|
|
.Pp
|
|
where
|
|
.Pa /mnt/mqueue
|
|
is a mount point.
|
|
.Pp
|
|
It is possible to define an entry in
|
|
.Pa /etc/fstab
|
|
that looks similar to:
|
|
.Bd -literal
|
|
null /mnt/mqueue mqueuefs rw 0 0
|
|
.Ed
|
|
.Pp
|
|
This will mount
|
|
.Nm
|
|
at the
|
|
.Pa /mnt/mqueue
|
|
mount point during system boot.
|
|
Using
|
|
.Pa /mnt/mqueue
|
|
as a permanent mount point is not advised as its intention
|
|
has always been to be a temporary mount point.
|
|
See
|
|
.Xr hier 7
|
|
for more information on
|
|
.Fx
|
|
directory layout.
|
|
.Pp
|
|
Some common tools can be used on the file system, e.g.:
|
|
.Xr cat 1 ,
|
|
.Xr chmod 1 ,
|
|
.Xr chown 8 ,
|
|
.Xr ls 1 ,
|
|
.Xr 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,
|
|
.Dq Li "touch /mnt/mqueue/myqueue" ,
|
|
will create a message queue named
|
|
.Pa 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
|
|
.Xr mq_open 2
|
|
system call to create a queue as it
|
|
allows the user to specify different attributes.
|
|
.Pp
|
|
To see the queue's attributes, just read the file:
|
|
.Pp
|
|
.Dl "cat /mnt/mqueue/myqueue"
|
|
.Sh SEE ALSO
|
|
.Xr mq_open 2 ,
|
|
.Xr nmount 2 ,
|
|
.Xr unmount 2 ,
|
|
.Xr mount 8 ,
|
|
.Xr umount 8
|
|
.Sh AUTHORS
|
|
This manual page was written by
|
|
.An "David Xu" Aq davidxu@FreeBSD.org .
|