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Date: | Thu, 26 Mar 1998 09:16:26 +0000 |
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Hi.
>
> At 03:36 AM 3/25/1998 Bill Cohane wrote:
> >
> >This little debug program will completely clean off track 0 on your
> >hardisk. Useful for removing drive BIOS overlays and such, and for
> >when drives don't seem to behave. Will also completely remove track 0
> >viruses. . . . .
>
> Bill:
>
> And here I thought DEBUG users had gone the way of
> EDLIN. <g> The mini-assembler of Debug is nice but it
> is a dangerous tool in inexperienced hands. I'd recommend
> Norton's Programmer's Guide to the IBM PC for beginners.
>
> I'm not certain this would fully work because the DDO uses
> a hidden partition table and fools DOS into thinking everything
> is copacetic. I don't know the exact location of the DDO but it
> may not be where your script is doing its work. Afterwards,
> when you think all is well, the hidden table may be "resurrected"
> like the undead in a horror movie and there you go again.
>
DEBUG is one forgotten but very useful program. I agree it
is dangerous, but it gives means to do low level things.
What Bill suggested is physically writing bytes in the
proper places, and in a context where partition tables and DOS
units have no meaning. So the only thing that can fool it is if
INT 13H code has been modified; even if the disk is not properly
recognized it should work, since it writes to first physical sector.
I would be surprised if it wouldn't work.
To not let INT 13H code to be intercepted, the best is to
boot from a DOS floppy, with no config/autoexec.
************************************
Javier Vizcaino. Ability Electronics. [log in to unmask]
Starting point: (-1)^(-1) = -1
Applying logarithms: (-1)*ln(-1) = ln(-1)
Since ln(-1) <> 0, dividing: -1 = 1
(ln(-1) is complex, but exists)
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