Date: Mon, 03 Jun 2002 20:00:33 +0300
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: JT Williams <jeffw AT darwin DOT sfbr DOT org>
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In-reply-to: <20020603142344.GA9949@kendall.sfbr.org> (message from JT
	Williams on Mon, 3 Jun 2002 09:23:44 -0500)
Subject: Re: create disk image using dd
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> Date: Mon, 3 Jun 2002 09:23:44 -0500
> From: JT Williams <jeffw AT darwin DOT sfbr DOT org>
> 
> Is there any way to do the equivalent of
> 
>         dd if=/dev/fd0 of=disk.img
> 
> with the djgpp port of `dd'?

DOS doesn't allow to access block devices directly.  So the only way
to do that is to use the DJGPP Filesystem Extensions feature to
redirect such requests to BIOS functions.  The current `dd' port
doesn't have such code, so it can only access disk files and character
devices.

I once wrote a prototype implementation of this (it needs work to cope
with bad blocks and other failures returned by BIOS functions).  I can
dust it off and mail it to you, if you are interested in working on
this.