Subject: Re: Floppy driver
To: David Jones <dej@eecg.toronto.edu>
From: Gregory Kritsch <gkritsch@sail.uwaterloo.ca>
List: amiga-dev
Date: 03/01/1994 12:24:16
> > Probably the best way to do this is to have the disklabel faker routine
> > report two partitions, a which skips track 0, and c which covers the
> > whole disk. You'd use 'a' in conjunction with adosfs, and 'c' with tar,
> > msdosfs, ufs, and everything else.
>
> You mean block 0, right? I don't want to skip a whole track!
Random thought based on SunOS:
Suns have three ``partitions'' on their floppies - a is track 0,
b is tracks 1-79, and c is the whole disk (a and b might be reversed).
I've never quite understood why, but...
The Amiga FFS reports the disktype as the first four bytes of sector 0
on the disk. Workbench displays icons labelled DF0:KICK (for example)
where KICK is a copy of those four bytes. DF0:BSD_ would certainly make
me think the disk is formatted. So there's a use for the a/b mpartitions
(stick BSD_ in a and use b for tar or ufs).
Most of the time, I can remember not to randomly format disks tha aren't
AmigaDOS (maybe it's because I use raw floppies for tar and MS-DOS disks
on a regular basis). If it becomes a problem, I can even stick a label on
them saying ``NetBSD disk''. This seems a much better solution to me than
wasting a bunch of sectors on the disk.
However, if someone really wants to get fancy, have a magical d partition
which skips track 0 and track 40, or the relevant portions thereof. Now,
except for the fact that we need some special code in fdformat to produce
a d-partitioned disk, I think everyone can be happy.
> David Jones, M.A.Sc student, Electronics Group (VLSI), University of Toronto
> email: dej@eecg.utoronto.ca, finger for more info/PGP public key
Gregory
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