Date: Wed, 17 Sep 1997 17:49:16 -0700 (PDT)
Message-Id: <199709180049.RAA25352@adit.ap.net>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
To: Brett Porter <bporter AT rabble DOT uow DOT edu DOT au>
From: Nate Eldredge <eldredge AT ap DOT net>
Subject: Re: ANNOUNCE: DJGPP port of UMoria v5.5.2
Cc: djgpp AT delorie DOT com (DJGPP)
Precedence: bulk

At 11:59  9/17/1997 +1000, Brett Porter wrote:
>> EMS?  I didn't think DJGPP could use EMS. In fact, I'm quite sure of it. Is
>> there something I don't know here?
>> 
>Not specifically it can't. It doesn't (specifically) use XMS or raw memory,
>either. It uses DPMI allocated memory, this is why you need a DPMI server to
>get the memory (eg Win95 or CWSDPMI). The Win95 server will give you any
>memory it can find (usually not a lot after it has taken its place in the
>system), whether it is EMS/XMS/whatever, it justs changes the allocation
>according to what you want.
>
>As for CWSDPMI, I'm not sure. I haven't tried running it on pre-MSDOS 6
>(ever since MSDOS 6.00, EMM386 adjusts the amount of EMS available according
>to how much XMS or EMS you want, before that the amount was fixed.) IF you
>tried allocating all of your extended memory as EMS using EMM386 in DOS 5, I
>don't know whether CWSDPMI would say there is none left or not. I'm sure it
>could.
No, I know about all of that. I guess I was thinking of the *original* EMS,
which was add-on boards accessed through a driver that mapped them by the
EMS scheme. This memory would not be part of the machine's usual address
space. Perhaps some people still use those boards (very unlikely, I know).
I'm quite sure that CWSDPMI or any other DPMI server, when presented with
memory accessible only by that means, would not be able to use it.

P.S. Even in DOS 5, EMM386 could allocate EMS and XMS from the same pool,
when in `auto' mode. I know because I still use it :) I'm too
cheap/lazy/anti-Microsloth to upgrade.

Nate Eldredge
eldredge AT ap DOT net