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Subject: Re: DEVFS vs "regular /dev"
To: terry@lambert.org (Terry Lambert)
Date: Wed, 20 Mar 1996 13:00:45 -0800 (PST)
From: "JULIAN Elischer" <julian@ref.tfs.com>
Cc: scrappy@ki.net, current@freebsd.org
In-Reply-To: <199603201933.MAA27577@phaeton.artisoft.com> from "Terry Lambert" at Mar 20, 96 12:33:42 pm
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all good but one question.....

> 
> > 	Just curious, but what is the advantage (and disadvantage, if any?)
> > of using devfs vs "regular /dev"?  My first thought would be that its
> > memory based instead of file system based, giving better performance, but
> > that's just a guess.
> 
[.... tons of reasons ]

> 
> This assumes that the file system abstractions currently in place
> change as well, since the /dev FS can't be mounted *after* the / FS
> has been mounted as an inferior FS --
why not?
you don't need a mounted /dev to mount root.
that's done specially.

> the /dev has to be there as
> an overlay mount (translucent FS), and that means FS changes to allow
> translucence and to divorce volume mappings from the need for a mount
> point (basically, a shadow / and /dev on which the devfs /dev is mounted
> and the real / is mounted over top of the shadow /).

I think that's not needed

julian