Date: Wed, 23 Nov 94 12:34:03 -0500
From: dj AT stealth DOT ctron DOT com (DJ Delorie)
To: wrh AT placer1 DOT wimsey DOT com
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: stack space goes boink


> Okay, this is a dumb question, could you post to the list a 
> thumbnail sketch of the differences between non-dpmi and 
> (un)non-dpmi?  Sort of the living non-dpmi?

In non-DPMI, go32 can put the stack at 0x7fffffff, and just not fill
in the memory inbetween that and the top of the heap.  In DPMI, you
have to allocate all the memory inbetween, so we put the stack UNDER
the heap (so that we can grow the allocated block to grow the heap),
and thus need to know how big it is.

Because we just can't map things anywhere (like the stack), we also
can't do graphics - because we map the graphics buffer at 0xd0000000,
or the 387 emulator - which is mapped to 0x90000000.  Even the
debugger is mapped to 0xa0000000, but in DPMI it has its own segment
and starts at zero.

DJ