Date:	Wed, 29 Jan 92 14:29:34 EST
From:	DJ Delorie <dj AT ctron DOT com>
To:	djgpp AT sun DOT soe DOT clarkson DOT edu
Subject:	go32 & DPMI
Status:	O

>I have heard from dj AT ctron DOT com that the djgpp mailing list is supposed
>to be quite active.  I was surprised to heard this, since I haven't

By "active", I meant that a lot of people were subscribing to it.

>Finally, DJ mentioned that go32 requires DPMI 1.0 but Windows only
>provides DPMI 0.9, so he won't be doing a port.  Just out of curiosity,
>I'd appreciate a quick description from anyone (DJ, if he's on the
>mailing list, but I don't want to bother him unnecessarily) of what
>features go32 needs from DPMI 1.0.  [I don't dispute his statement in
>any way -- I'd just like to know.]

DPMI 0.9 is effectively a 286 implementation.  It does not provide
support for the flat memory model that go32 provides.  Go32 takes
great advantage of the paging mechanism of the 386 to make memory
appear all over the 32-bit address space, like code at 0, data at
0x400000, stack down from 0x7fffffff, physical memory at 0xe0000000,
svga memory at 0xd0000000, etc.  DPMI 0.9 does not allow the
application to control memory to this granularity.  In fact, 0.9
doesn't even give understand most of the 386 features at all - you
can't request memory mapping, you can't figure out where the idt/gdt
are, etc.

DPMI 1.0, on the other hand, includes all the extra functions required
to fully excersize the 386 features.

DJ
dj AT ctron DOT com
Life is a banana.

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