Re: devfs vs. udev

[tabris <tabris@tabris.net>]

On Tuesday 07 October 2003 08:38 am, Måns Rullgård wrote:
> I noticed this in the help text for devfs in 2.6.0-test6:
>
> 	  Note that devfs has been obsoleted by udev,
> 	  <http://www.kernel.org/pub/linux/utils/kernel/hotplug/>.
> 	  It has been stripped down to a bare minimum and is only provided for
> 	  legacy installations that use its naming scheme which is
> 	  unfortunately different from the names normal Linux installations
> 	  use.
>
> Now, this puzzles me, for a few of reasons.  Firstly, not long ago,
> devfs was spoken of as the way to go, and all drivers were rewritten
> to support it.  Why this sudden change?  Secondly, that link only
> leads me to a package describing itself as an experimental
> proof-of-concept thing, not to be used for anything serious.  How can
> something that incomplete obsolete a working system like devfs?
> Thirdly, udev appears to respond to hotplug events only.  How is it
> supposed to handle device files not corresponding to any physical
> device?  Finally, I quite liked the idea of a virtual filesystem for
> /dev.  It reduced the clutter quite a bit.  As for the naming scheme,
> it could easily be changed.
My word is hardly authoritative, but istr hearing that the original 
devfs-maintainer has abandoned this code (probably after multiple 
complaints about it being badly implemented, full of bugs, locking 
issues/races, etc).

Not having used it with 2.6 yet, I don't know much about it's status in 
that tree.

So, although devfs may still work, and even be in a better condition than 
udev (at present); no longer maintained (and little intention of 
changing) may be considered equivalent to obsolete.
--
tabris
-
	Max told his friend that he'd just as soon not go hiking in the hills.
Said he, "I'm an anti-climb Max."
	[So is that punchline.]