Re: FreeBSD devfs support on NetBSD 5.0

[der Mouse <mouse%Rodents-Montreal.ORG@localhost>]

> (4) Structurally, permissions are (and should be) properties of the
> device driver, not of some intermediate devfs object.

I very strongly disagree with this.  For example, I see it as totally
reasonable to have different permissions on the very same device in
/dev and /ftp-chroot/dev and /ntp-chroot/dev (most likely, the chroot
jails get read-only versions of what's read-write in /dev, but not
necessarily).

> Some devices have (or should have) fixed permissions; for example,
> "chmod 711 /dev/null" serves no purpose but to render the system
> dysfunctional and there's no need to allow it at all...

On most systems, yes.  But "Unix does not prevent you from doing stupid
things because that also prevents you from doing clever things".  Are
you certain there is no use, anywhere, under any set of special
circumstances, for unusual permissions on /dev/null?  I'm not.

> let alone go to a lot of effort to make its effects persistent.

Again, I disgaree.  The major reason to support that is that it is an
automatic consequence of something much more useful and important -
persistent mode bits on *other* entries in /dev.  I really really don't
like the idea of duplicating permission changing and saving code in
each device driver rather than doing it once.

> And finally, I'm still not entirely clear on what the benefit of a
> devfs is supposed to be.  [...]

I entirely agree with you here.  I see devfs as a solution looking for
a problem.

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