devfs(5) [freebsd man page]

DEVFS(5)						      BSD File Formats Manual							  DEVFS(5)

NAME

     devfs -- device file system

SYNOPSIS

     devfs   /dev    devfs rw 0 0

DESCRIPTION

     The device file system, or devfs, provides access to kernel's device namespace in the global file system namespace.  The conventional mount
     point is /dev.

     The file system includes several directories, links, symbolic links and devices, some of which can also be written.  In a chroot'ed environ-
     ment, devfs can be used to create a new /dev mount point.

     The mknod(8) tool can be used to recover deleted device entries under devfs.

     The fdescfs(5) filesystem is an alternate means for populating /dev/fd.  The character devices that both devfs and fdescfs(5) present in
     /dev/fd correspond to the open file descriptors of the process accessing the directory.  devfs only creates files for the standard file
     descriptors 0, 1 and 2.  fdescfs(5) creates files for all open descriptors.

     The options are as follows:

     -o options
	     Use the specified mount options, as described in mount(8).  The following devfs file system-specific options are available:

	     ruleset=ruleset
		     Set ruleset number ruleset as the current ruleset for the mount-point and apply all its rules.  If the ruleset number ruleset
		     does not exist, an empty ruleset with the number ruleset is created.  See devfs(8) for more information on working with devfs
		     rulesets.

FILES

     /dev	The normal devfs mount point.

EXAMPLES

     To mount a devfs volume located on /mychroot/dev:

	   mount -t devfs devfs /mychroot/dev

SEE ALSO

     fdescfs(5), devfs(8), mount(8)

HISTORY

     The devfs file system first appeared in FreeBSD 2.0.  It became the preferred method for accessing devices in FreeBSD 5.0 and the only method
     in FreeBSD 6.0.  The devfs manual page first appeared in FreeBSD 2.2.

AUTHORS

     The devfs manual page was written by Mike Pritchard <mpp@FreeBSD.org>.

BSD
								 February 9, 2012							       BSD

DEVFS.CONF(5)						      BSD File Formats Manual						     DEVFS.CONF(5)

NAME

     devfs.conf -- boot-time devfs configuration information

DESCRIPTION

     The devfs.conf file provides an easy way to set ownership and permissions, or create links for devices available at boot.

     It does not work for devices plugged in and out after the system is up and running, e.g. USB devices.  See devfs.rules(5) for setting owner-
     ship and permissions for all device nodes, and devd.conf(5) for actions to be taken when devices are attached or detached.

     Lines starting with a hash sign ('#') and empty lines are ignored.  The lines that specify devfs.conf rules consist of three parameters sepa-
     rated by whitespace:

     action  The action to take for the device.  The action names are only significant to the first unique character.

     devname
	     The name of the device created by devfs(5).

     arg     The argument of the action.

     The actions currently supported are:

     link    This action creates a symbolic link named arg that points to devname, the name of the device created by devfs(5).

     own     This action changes the ownership of devname.  The arg parameter must be in the form of an owner:group pair, in the same format used
	     by chown(8).

     perm    This action changes the permissions of devname.  The arg parameter must be a mode as explained in chmod(1).

FILES

     /etc/devfs.conf
     /usr/share/examples/etc/devfs.conf

EXAMPLES

     To create a /dev/cdrom link that points to the first SCSI(4) CD-ROM, the following may be added to devfs.conf:

	   link    cd0	   cdrom

     Similarly, to link /dev/cdrom to the first ATAPI CD-ROM device, the following action may be used:

	   link    acd0    cdrom

     To set the owner of a device, the own action may be specified:

	   own	   cd0	   root:cdrom

     To set the permissions of a device, a perm action should be used:

	   perm    cd0	   0660

SEE ALSO

     chmod(1), devd.conf(5), devfs(5), devfs.rules(5), chown(8)

AUTHORS

     This manual page was written by Roland Smith <rsmith@xs4all.nl>.

BSD
								   May 17, 2005 							       BSD