Subject: x86 disklabel and the raw partition ...
To: None <current-users@netbsd.org>
From: Andrew Cagney <cagney@highland.com.au>
List: current-users
Date: 09/26/1994 11:53:50
Hello,

	Ref: NetBSD 1.0_BETA (GENERICAHA) #3: Mon Aug  1 16:48:16 PDT 1994

Recently there was a discussion about disklabel (x86) not working.  Just
tried it myself and noticed the following ...

For the x86, disklabel is built to use partition `d' as the raw
partition (RAWPARTITION in Makefile).  The /etc/disktab file, configures
the floppy disk as:

	root@bunyip# /sbin/disklabel -r /dev/rfd0c
	. . .
	3 partitions:
	#        size   offset    fstype   [fsize bsize   cpg]
	  a:     2400        0    unused      512  4096         # (Cyl.    0 - 79)
	  b:     2400        0    unused      512  4096         # (Cyl.    0 - 79)
	  c:     2400        0    unused      512  4096         # (Cyl.    0 - 79)

vs a hard disk partitioned when NetBSD-0.9 was installed:

	4 partitions:
	#        size   offset    fstype   [fsize bsize   cpg]
	  a:   976225        0    4.2BSD     1024  8192    16   # (Cyl.    0 - 2296)
	  b:    83300   976225      swap                        # (Cyl. 2297 - 2492)
	  c:  1059525        0    unused        0     0         # (Cyl.    0 - 2492)
	  d:  1059525        0    unused        0     0         # (Cyl.    0 - 2492)

so for floppy disk, `d' is empty.  The consequence is that instead of:

	/sbin/disklabel -r -w fd0 5in
	/sbin/disklabel -B fd0

working (IO error on /dev/fd0d) you need to specify:

	/sbin/disklabel -r -w /dev/rfd0c 5in
	/sbin/disklabel -B /dev/rfd0c

			interesting,

						Andrew