Re: Help about MBR and BOOT sectors

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Article #358

#358

From: John S. Fine
Date: Tue, 14 Jul 1998 00:00

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b2a wrote:
>
> At least BSD and DOS both expect to be called with SI pointing to their
> entry in the partition table....doesn't seem to matter where in memory you
> leave the table image, so long as the SBR code can see it.  If you do this,
> you don't actually need to leave the partition table in it's usual place in
> the MBR -- everything will boot ok

  I don't know about BSD, but when I tested with DOS it need its
partition
entry BOTH in memory (pointed to by si) and in the MBR.

  An early version of my multi-boot-mbr did not rewrite the modified mbr
back to disk.  It just left it in RAM.  Unixware could be booted that
way, but DOS required that its active bit be set in its partition entry
on disk.
-- 
http://www.erols.com/johnfine/
http://www.geocities.com/SiliconValley/Peaks/8600/

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From: "John S. Fine" <johnfine@erols.com>
Subject: Re: Help about MBR and BOOT sectors
Date: 1998/07/14
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