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DEVFS(4)		     Kernel Interfaces Manual			DEVFS(4)

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 name-
     space in the global file system namespace.  The conventional mount point is
     /dev.

     The file system includes several directories, links, symbolic links and de-
     vices, some of which can also be written.	In a chroot'ed environment,  de-
     vfs(8) 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(4) filesystem is an alternate	means  for  populating	/dev/fd.
     The  character  devices  that  both devfs and fdescfs(4) present in /dev/fd
     correspond to the open file descriptors of the process accessing the direc-
     tory.  devfs only creates files for the standard file descriptors 0, 1  and
     2.  fdescfs(4) 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(4), devfs(8), mount(8), make_dev(9)

HISTORY
     The  devfs  file  system first appeared in FreeBSD 2.0.  It became the pre-
     ferred 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>.

FreeBSD 15.1			  June 30, 2022 			DEVFS(4)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=devfs&sektion=4&manpath=FreeBSD+15.1-RELEASE+and+Ports.quarterly>

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