From owner-freebsd-current  Sun Dec  9 18:51:35 2001
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Date: Sun, 09 Dec 2001 18:51:34 -0800
From: Terry Lambert <tlambert2@mindspring.com>
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To: Peter Wemm <peter@wemm.org>
Cc: Joerg Wunsch <joerg_wunsch@uriah.heep.sax.de>,
	freebsd-current@FreeBSD.ORG
Subject: Re: cvs commit: src/sys/kern subr_diskmbr.c
References: <20011210005928.9538A3810@overcee.netplex.com.au>
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> Joerg Wunsch wrote:
> > Mike Smith <msmith@FreeBSD.ORG> wrote:
> > >  - The MBR partition table is not "obsolete", it's a part of the PC
> > >    architecture specification.
> >
> > Its design is antique.  Or rather: it's missing a design.  See other
> > mail for the reasons.  For FreeBSD, it's obsolete since we don't need
> > to rely on fdisk slices.  (Or rather: it's optional.  We can make good
> > use of it when it's there, but we don't need to insist on it being
> > there.)

FWIW: The MBR layout is documented in great gory detail in chapter 6
of the PReP specififcation, which I believe is now available on line
from the PowerPC folks, Apple, and Motorolla, and also as an IBM
"redbook".  It discusses everything, including the LBA fields, and
sharing disks between PPC (running in Motorolla byte order) and x86
machines (running a DOS-derived OS).

-- Terry

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