Date: Sat, 6 Jun 92 15:08:55 EDT
From: DJ Delorie <dj AT ctron DOT com>
To: bwhite AT inmet DOT camb DOT inmet DOT com
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: GCC and Windows/DPMI

*gcc* is just a compiler.  djgpp is more than just gcc - it includes
the software required to *run* gcc.  Since gcc expects a 32-bit
virtual memory environment and DOS doesn't even come close, you have
to figure out a way to provide one yourself.  This is the job of go32,
which puts the 386 into protected mode and services system requests
from the application (gcc, for example).  VCPI and DPMI are protocols
for go32-style programs to cooperate together (go32 currently
cooperates with QEMM, for example).  Windows is a go32-style program,
but does not support a protocol robust enough for go32 to continue to
provide it's services to go32-run applications (virtual memory, stack,
etc), so go32 cannot run applications in a Windows environment.

The word I heard from MicroSoft is that they don't plan on supporting
DPMI 1.0 in Windows 3.1 (I think it's a monoboly-building decision,
myself), so don't expect go32 to run in it.



DJ
dj AT ctron DOT com
Life is a banana.