Date: Tue, 16 Sep 1997 15:34:52 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: baldo AT chasque DOT apc DOT org
cc: Leath Muller <leathm AT solwarra DOT gbrmpa DOT gov DOT au>, djgpp AT delorie DOT com
Subject: Re: 32bit DOS.
In-Reply-To: <3.0.1.32.19970915155722.0068abb8@chasque.apc.org>
Message-ID: <Pine.SUN.3.91.970916152922.25597B-100000@is>
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On Mon, 15 Sep 1997 baldo AT chasque DOT apc DOT org wrote:

> 	I have to load win 95, then put the DOS prompt. In my slow machine 
> this is tedious.

Why can't you just prevent Windows from automatically loading the GUI? 
Edit your msdos.sys so that the startup menu is always shown, then choose
"Command prompt" whenever you need to boot into plain DOS 7.  That's all
there is to it. 

> 	Talking about this topic, a question has come to me: When a DOS protected
> memory program (such for example a DJGPP program) run under the Win 95 DOS
> prompt, and for example uses the hardisk, in normal Real Mode DOS (or pure
> DOS) it switches to real mode, do the operation and then switch to
> protected mode again, but in the DOS box under Win95, it switchs to real
> mode or V86 mode or it do not switch to any mode and do the operation in
> protected mode?

It's actually much more complex than that.  Windows catches all the
attempts to switch to real mode and does whatever it likes (depending on
the interrupt that's issued and the type of the program which does that). 
Usually, the DOS call goes from the DJGPP program directly into the 32-bit
protected-mode code.  Some calls are caught by IFSHLP.SYS driver in real 
mode and thunked back to the protected-mode layers of Windows.