Subject: Re: The obvious inherent superiority of SVR4 device naming...
To: None <>
From: der Mouse <mouse@Collatz.McRCIM.McGill.EDU>
List: current-users
Date: 12/23/1994 11:39:07
>> Tagged?  Tagged where?  At least on the SPARC port, and indeed on
>> all systems I've ever used, swap partitions are not tagged in any
>> way anywhere, [...except maybe /etc/fstab].

> What about in the disk label?

> #        size   offset    fstype   [fsize bsize   cpg]
> ...
>   b:    32886    32886      swap                        # (Cyl.   58 - 115)
> ...

NetBSD/sparc uses Sun disklabels.  Sun disklabels have very little
per-partition information; see /sys/arch/sparc/scsi/sun_disklabel.* in
the 1.0 release or <sun/dklabel.h> on SunOS 3.5 or 4.1.2.  All they
have is an offset from the beginning of the pack, in cylinders, and a
size, in sectors.  (Why the different units, I have no idea.)

If the Sun-to-NetBSD conversion code synthesizes partition types, it
must be guessing, perhaps depending on convention (eg, a=root b=swap)
or perhaps looking at what partition is currently in use for what....

IRIX (on SGIs) does have typed partitions, it turns out (I didn't know
this), but "swap" is not one of the available types in the release we
have.  The only type I see in the include file that would be
appropriate for a swap partition is "raw", and that appears to be
what's used.  Whether the kernel is willing to swap on a partition with
any other type I don't know.

The only other partitioning setup I have used is the old 4.3 one, where
partitions are compiled into the relevant drivers.  These partitions
were untyped.

					der Mouse