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From:	Charles Sandmann <sandmann AT clio DOT rice DOT edu>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Easy question about pseudo registers
Date:	Tue, 05 Mar 2002 23:16:35 CST
Organization:	Rice University, Houston TX
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> Well I know that the instruction length will vary, but right now I just
> concentrating on the instruction in my crash.exe program, which is 4
> bytes long.

Okay...

> Also, I thought that all of the real mode reg values were passed on to
> _go32_dpmi_registers *r and that any changes made to r-> register would
> be passed back to the real registers.

You are probably getting tangled up with what the _go32_dpmi ...
wrapper does for you.  The DPMI spec says it's the user's responsibility
to set CS:IP in the register block - you need to read the DPMI spec
carefully then look at the source to the wrapper routine to see if 
it does what you want - or maybe you need to modify it or write your
own wrapper.  I don't have time to look at it right now, sorry.

> So if that isn't the case, do you know, or have an idea, of how I can
> access the real mode registers?

Please grab djlsr203.zip and look in src/libc/go32/gormcb.c (also 
available from cvs web access for a single file from www.delorie.com)
to see what it's doing for you.

A quick glance seems to me that it always loads CS:IP from the top of
the real mode stack, which is definitely the wrong thing in your case.
You probably need to write your own assembly wrapper.

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