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.\" Copyright (c) 2004 Roland Smith <rsmith@xs4all.nl>
.\" 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, 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.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR OR CONTRIBUTORS BE LIABLE
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" $FreeBSD$
.\"
.Dd May 25, 2019
.Dt DEVFS.CONF 5
.Os
.Sh NAME
.Nm devfs.conf
.Nd boot-time devfs configuration information
.Sh DESCRIPTION
The
.Nm
file provides an easy way to set ownership and permissions, or create
links for devices available at boot.
.Pp
It does not work for devices plugged in and out after the system is up
and running, e.g.\& USB devices.
See
.Xr devfs.rules 5
for setting ownership and permissions for all device nodes, and
.Xr devd.conf 5
for actions to be taken when devices are attached or detached.
.Pp
Lines starting with a hash sign
.Pq Ql #
and empty lines are ignored.
The lines that specify
.Nm
rules consist of three parameters separated by whitespace:
.Bl -tag -width indent
.It Ar action
The action to take for the device.
The action names are only significant to the first unique character.
.It Ar devname
The name of the device created by
.Xr devfs 5 .
.It Ar arg
The argument of the
.Ar action .
.El
.Pp
The actions currently supported are:
.Bl -tag -width indent
.It Ic link
This action creates a symbolic link named
.Ar arg
that points to
.Ar devname ,
the name of the device created by
.Xr devfs 5 .
.It Ic own
This action changes the ownership of
.Ar devname .
The
.Ar arg
parameter must be in the form of an
.Ar owner Ns : Ns Ar group
pair, in the same format used by
.Xr chown 8 .
.It Ic perm
This action changes the permissions of
.Ar devname .
The
.Ar arg
parameter must be a
.Ar mode
as explained in
.Xr chmod 1 .
.El
.Sh FILES
.Bl -tag -compact -width Pa
.It Pa /etc/devfs.conf
.It Pa /usr/share/examples/etc/devfs.conf
.El
.Sh EXAMPLES
To create a
.Pa /dev/cdrom
link that points to the first CD-ROM,
the following may be added to
.Nm :
.Bd -literal -offset indent
link	cd0	cdrom
.Ed
.Pp
To set the owner of a device, the
.Ic own
action may be specified:
.Bd -literal -offset indent
own	cd0	root:cdrom
.Ed
.Pp
To set the permissions of a device, a
.Ic perm
action should be used:
.Bd -literal -offset indent
perm	cd0	0660
.Ed
.Sh SEE ALSO
.Xr chmod 1 ,
.Xr devd.conf 5 ,
.Xr devfs 5 ,
.Xr devfs.rules 5 ,
.Xr chown 8
.Sh AUTHORS
This manual page was written by
.An Roland Smith Aq Mt rsmith@xs4all.nl .