150 lines
3.8 KiB
Groff
150 lines
3.8 KiB
Groff
.\" Copyright (c) 1996
|
|
.\" Mike Pritchard <mpp@FreeBSD.org>. All rights reserved.
|
|
.\"
|
|
.\" Copyright (c) 1992, 1993, 1994
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software donated to Berkeley by
|
|
.\" Jan-Simon Pendry.
|
|
.\"
|
|
.\" 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, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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 February 9, 2012
|
|
.Dt DEVFS 5
|
|
.Os
|
|
.Sh NAME
|
|
.Nm devfs
|
|
.Nd device file system
|
|
.Sh SYNOPSIS
|
|
.Bd -literal
|
|
devfs /dev devfs rw 0 0
|
|
.Ed
|
|
.Sh DESCRIPTION
|
|
The device file system, or
|
|
.Nm ,
|
|
provides access to kernel's device
|
|
namespace in the global file system namespace.
|
|
The conventional mount point is
|
|
.Pa /dev .
|
|
.Pp
|
|
The file system includes several directories, links, symbolic links
|
|
and devices, some of which can also be written.
|
|
In a chroot'ed
|
|
environment,
|
|
.Nm
|
|
can be used to create a new
|
|
.Pa /dev
|
|
mount point.
|
|
.Pp
|
|
The
|
|
.Xr mknod 8
|
|
tool can be used to recover deleted device entries under
|
|
.Nm .
|
|
.Pp
|
|
The
|
|
.Xr fdescfs 5
|
|
filesystem is an alternate means for populating
|
|
.Pa /dev/fd .
|
|
The character devices that both
|
|
.Nm
|
|
and
|
|
.Xr fdescfs 5
|
|
present in
|
|
.Pa /dev/fd
|
|
correspond to the open file descriptors of the process
|
|
accessing the directory.
|
|
.Nm
|
|
only creates files for the standard file descriptors
|
|
.Pa 0 ,
|
|
.Pa 1
|
|
and
|
|
.Pa 2 .
|
|
.Xr fdescfs 5
|
|
creates files for all open descriptors.
|
|
.Pp
|
|
The options are as follows:
|
|
.Bl -tag -width indent
|
|
.It Fl o Ar options
|
|
Use the specified mount
|
|
.Ar options ,
|
|
as described in
|
|
.Xr mount 8 .
|
|
The following devfs file system-specific options are available:
|
|
.Bl -tag -width indent
|
|
.It Cm ruleset Ns No = Ns Ar ruleset
|
|
Set ruleset number
|
|
.Ar ruleset
|
|
as the current ruleset for the mount-point and apply all its rules.
|
|
If the ruleset number
|
|
.Ar ruleset
|
|
does not exist, an empty ruleset with the number
|
|
.Ar ruleset
|
|
is created.
|
|
See
|
|
.Xr devfs 8
|
|
for more information on working with devfs rulesets.
|
|
.El
|
|
.El
|
|
.Sh FILES
|
|
.Bl -tag -width /dev/XXXX -compact
|
|
.It Pa /dev
|
|
The normal
|
|
.Nm
|
|
mount point.
|
|
.El
|
|
.Sh EXAMPLES
|
|
To mount a
|
|
.Nm
|
|
volume located on
|
|
.Pa /mychroot/dev :
|
|
.Pp
|
|
.Dl "mount -t devfs devfs /mychroot/dev"
|
|
.Sh SEE ALSO
|
|
.Xr fdescfs 5 ,
|
|
.Xr devfs 8 ,
|
|
.Xr mount 8 ,
|
|
.Xr make_dev 9
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
file system first appeared in
|
|
.Fx 2.0 .
|
|
It became the preferred method for accessing devices in
|
|
.Fx 5.0
|
|
and the only method in
|
|
.Fx 6.0 .
|
|
The
|
|
.Nm
|
|
manual page first appeared in
|
|
.Fx 2.2 .
|
|
.Sh AUTHORS
|
|
The
|
|
.Nm
|
|
manual page was written by
|
|
.An Mike Pritchard Aq Mt mpp@FreeBSD.org .
|