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Date: Wed, 16 May 2001 14:36:44 -0700
From: "H. Peter Anvin" <hpa@transmeta.com>
Organization: Transmeta Corporation
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To: Richard Gooch <rgooch@ras.ucalgary.ca>
CC: Geert Uytterhoeven <geert@linux-m68k.org>,
        Alan Cox <alan@lxorguk.ukuu.org.uk>,
        Ingo Oeser <ingo.oeser@informatik.tu-chemnitz.de>,
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        Jeff Garzik <jgarzik@mandrakesoft.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        viro@math.psu.edu
Subject: Re: LANANA: To Pending Device Number Registrants
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Richard Gooch wrote:
> >
> > Because you are now, once again, tying two things that are
> > completely and utterly unrelated: device classification and device
> > name.  It breaks every time someone comes out with a new device
> > which is "kind of like an old device, but not really," like
> > CD-writers (which was kind-of-like WORM, kind-of-like CD-ROM) and
> > DVD (kind-of-like CD)...
> 
> But all devices which export a CD-ROM interface will do so. So the
> device node that is associated with the CD-ROM driver will export
> CD-ROM semantics, and the trailing name will be "/cd".
> 
> Other interfaces a device exports, such as a CD-RW, appear as a
> different device node ("generic" for SCSI, because we have no CD-RW
> classification at this point).
> 
> My scheme works already, and works reliably. Nothing had to be done to
> support the CD-ROM interface to CD-RW and DVD devices.
> 

It's still completely braindamaged: (a) these interfaces aren't
disjoint.  They refer to the same device, and will interfere with each
other; (b) it is highly undesirable to tie the naming to the interfaces
in this way.  It further restricts the namespaces you can export, for one
thing.

	-hpa

-- 
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt