Date:	Sun, 16 Sep 2001 09:31:59 +0200 (IST)
From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender:	eliz AT is
To:	Mark & Candice White <mhewii AT home DOT com>
cc:	djgpp AT delorie DOT com
Subject:	Re: addressing question
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On Sun, 16 Sep 2001, Mark & Candice White wrote:

> 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 is not true: the DJGPP run-time environment is not flat, it's 
segmented.  However, the main (data/code) segment is very large and can 
grow as needed, to become as large as the underlying DPMI host allows.

So as long as you stay with ``normal'' C code, you can make-believe that 
you are running in a flat address space.  But as soon as you try to 
access conventional memory or some memory-mapped device, you will 
discover the segmented nature of the DJGPP address space which will force 
you to use _farpeekb, dosmemput, movedata, and other similar functions 
that set either FS or GS to point to another segment.

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