Date: Wed, 21 Jan 1998 16:07:00 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Sérgio Vale e Pace <space AT gold DOT com DOT br>
cc: djgpp AT delorie DOT com
Subject: Re: Fat CS?
In-Reply-To: <34C521FA.5BDC6A6D@gold.com.br>
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On Tue, 20 Jan 1998, Sérgio Vale e Pace wrote:

>     if the fat DS trick can be used to CS to call real mode functions
> (the vbe direct bank switch in case) ?

It won't help you.  The ``fat'' hack is only about being able to access a 
given address.  But there is another fundamental incompatibility between 
real- and protected-mode code, and that is that the way memory addresses 
are interpreted.  So you might be able to call the address in lower 
memory, but your program will most probably crash when the real mode code 
does something that's illegal in PM, such as loading an arbitrary value 
into a segment register.

In short: forget it.