From: bwhite AT inmet DOT camb DOT inmet DOT com (Bill White)
Subject: GCC and Windows/DPMI
To: djgpp AT sun DOT soe DOT clarkson DOT edu (The DOS GCC list)
Date: Fri, 5 Jun 92 18:02:36 EDT

I know that the djgpp documentation tells me that djgpp is VCPI compliant,
and that DPMI 0.9 does not provide enough services to make gcc work.  However,
I have not seen in the documentation a thorough discussion of this.  It
seems to me that the compiler itself does not need to be VCPI or DPMI or
XMS or JOESVMPROTOCOL compliant - it just generates assembly language.
The assembler and linker are just programs - they do some computation
by reading input and writing output.  They don't do anything fancy with
task or memory management, so that can't be the problem.  (Actually one
version of the Unix loader I saw did vectored writes with readv(2) to write
the text, data and symbol table out, but since the kernel serialized
readv(2) calls in 4.2 anyway, it didn't make much difference.  This could
be fixed easily enough.)  My uneducated guess would be that something in
the libraries need a service which DPMI 0.9 doesn't supply.

I would like the answers to these and other questions.  I am afraid that
this is an IAQ (Incessantly Asked Query) and that asking it will just
drag out a long discussion which everybody has already heard.  If so,
please forgive me.

					Peace,
					Bill White
					<bwhite AT cobra DOT camb DOT inmet DOT com>

P.S. Is Windows 3.1 DPMI 1.0 Compliant?  Does that make any difference?
P.P.S.  I am thinking about buying MSC 7.0.  The $139 price tag is almost
too good to pass up.  However, I would like to hear other opinions
about it.  I suspect that this is not a djgpp list compliant question,
so please make replies to me individually by email.  I will summarize by
email for anybody who asks for a summary.