Subject: Re: kern/8515: Acorn CD-ROMs
To: Chris G. Demetriou <>
From: Stephen Borrill <>
List: netbsd-bugs
Date: 09/30/1999 10:58:51
On Wed 29 Sep, Chris G. Demetriou wrote:
> writes:
> > N.B. On a non-Acorn CDROM, the behaviour is entirely backward compatible;
> > the Acorn enhancments are ignored if the system dependent area is not
> > exactly 32 bytes long and doesn't begin with the 10 characters ARCHIMEDES
> > (non-terminated).
> If these changes are truly "safe" on non-Acorn CD-ROMs, then they
> should probably be enabled by default, just like Rockridge extensions,
> and disabled via a flag.

I entirely agree. The extra translation does the above two checks before
doing anything else and it's unlikely that the ARCHIMEDES magic string
will appear on other CDs.

I thought I'd err on the side of safety. Plus, I remember Wolfgang Solfrank
having the following to say back on 23/3/98, though I think he misunderstood
the issues: 

> Hmm, does this really mean what I read into it?  Namely that you are
> munging the filename as read from the CD in order to accomodate some
> broken software that doesn't supply the correct filenames as recorded
> on the disk?  If so, such a hack is definitly NOT going into the NetBSD
> cd9660 support (as long as I can help it anyway).

> Something I might consider (albeit I'm still pretty sure that I'd get
> ache in my stomach implementing it) is using a filesystem layer to
> translate names.  Note that this is just an idea that occured to me,
> haven't thought about it too much yet.

Problem is that ! isn't a valid ISO character and filenames beginning
with ! are very important to RISCOS. Also, filetype is not determined 
by the filename extension. Filetypes are also very important to RISCOS.

Dr. Stephen Borrill, Director and Principal Engineer
Precedence Technologies Ltd             Tel: +44 (0) 1223 562 500
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