Name:          devfs
Version:       99.21
Kernelver:     2.2.20
Status:        9
Author:        Richard Gooch <rgooch@atnf.csiro.au>
Description:   Device File System
Date:          4-DEC-2001
Descfile-URL:  ftp://ftp.atnf.csiro.au/pub/people/rgooch/linux/kernel-patches/v2.2/devfs.desc
Download-URL:  ftp://ftp.atnf.csiro.au/pub/people/rgooch/linux/kernel-patches/v2.2/devfs-patch-current.gz
Homepage-URL:  http://www.atnf.csiro.au/~rgooch/linux/kernel-patches.html
Manual-URL:    http://www.atnf.csiro.au/~rgooch/linux/docs/devfs.html

Devfs is an alternative to "real" character and block special devices
on your root filesystem. Kernel device drivers can register devices by
name rather than major and minor numbers. These devices will appear in
the devfs automatically, with whatever default ownership and
protection the driver specified.

NOTE that devfs is entirely optional. If you prefer the old disc-based
device nodes, then simply leave CONFIG_DEVFS_FS=n (the default). In
this case, nothing will change.

There are two aspects to devfs: one is the underlying device
namespace, which is a namespace just like any mounted filesystem. The
other aspect is the filesystem code which provides a view of the
device namespace. The reason I make a distinction is because the devfs
can be mounted many times, with each mount showing the same device
namespace. Changes made are global to all mounted devfs filesystems.
Also, because the devfs namespace exists without any devfs mounts, you
can easily mount the root filesystem by referring to an entry in the
devfs namespace.