Date: Sun, 16 Sep 2001 21:46:33 +0300
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: "Mark & Candice White" <mhewii AT home DOT com>
Message-Id: <2593-Sun16Sep2001214633+0300-eliz@is.elta.co.il>
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CC: djgpp AT delorie DOT com
In-reply-to: <uZ1p7.113099$K6.46338882@news2> (mhewii@home.com)
Subject: Re: addressing question
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> From: "Mark & Candice White" <mhewii AT home DOT com>
> Newsgroups: comp.os.msdos.djgpp
> Date: Sun, 16 Sep 2001 13:40:42 GMT
> 
> The code is not running in the normal DJGPP run-time environment.
> That is made with the help of DOS and DPMI. Neither are there.
> Just a simple flat mem model with 3 GDT entries: code, data, and video.
> 
> You are quite right about how djgpp is normaly used but dima made
> it clear that DJGPP is being used more as a pure port of gcc hosted
> in dos. My responce was in regards to the exact use it is being used for,
> and as such is correct.

If so, your wording was inaccurate and misled me into thinking you are
talking about the normal DJGPP runtime:

> > > GCC and its dos port DJGPP are made for flat mem models
> > > where ds,es,fs,gs,ss all point to the same mem, and cs is all so
> > > the same phisical mem.

This explicitly talks about DJGPP, not just GCC.  It also specifically
says that FS and GS are set up to the same segment as DS, SS, and CS,
which is not true in the DJGPP setup.  If Dima sets up the environment
differently, and doesn't use the DJGPP library and startup code, then
he is not using DJGPP at run time.

> As an aside I do still belive that DJGPP is made for flat mem model.

I don't understand how can you believe that, since facts contradict
this.  For starters, you can't even access the entire address space
without setting the segment limit to -1 and using the address wrap.
This is not what the flat model is about.

> DJGPP uses a flat mem model, it is just its hosted OS that does
> not.

Not true: the DJGPP library and the startup code themselves make
extensive use of segmentation, and so does the debug support.

> Do not worry about debating it, you will not change my mind
> and I will not likely change yours, so just belive your right.

This is not a question of belief.  There are facts out there, so the
issue can (and should) be unequivocally decided to be one or the
other.