Comments: Authenticated sender is <mert0407 AT sable DOT ox DOT ac DOT uk>
From: "George Foot" <george DOT foot AT merton DOT oxford DOT ac DOT uk>
To: Endlisnis <s257m AT unb DOT ca>
Date: Thu, 27 Aug 1998 18:39:43 +0000
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Subject: Re: Largest DJGPP project
Reply-to: george DOT foot AT merton DOT oxford DOT ac DOT uk
CC: djgpp AT delorie DOT com
Message-Id: <E0zC62r-0002u7-00@sable.ox.ac.uk>
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On 26 Aug 98 at 19:09, Endlisnis wrote:

> Eli Zaretskii wrote:
> 
> > CWSDPMI supports more than 256MB (it's 256MB virtual plus whatever you
> > have physically available).
> 
>     I have a question about the 'swap' space reported by go32-v2.exe.  I found
> a copy of 'go32.exe' which came with some freeware that I got of some site,
> and, when run said:
> 
> go32 version 1.12 Copyright (C) 1994 DJ Delorie
> Lowest version I can run is 1.08
> go32.exe usage: go32 [-d {debugger}] [{program} [{options} . . . ]]
> go32.exe build time was Thu Aug 04 19:52:27 1994
> DPMI memory available: 11612 Kb
> Swap space available: 429024 Kb

"go32" is the DOS extender used by djgpp v1.  I don't remember 
exactly, but IIRC you had to run go32 passing the name of your COFF 
image to run it.  DJGPP v2 uses the stub instead, and no extender.

The two versions get their memory in different ways.  v1 could get it
from a variety of sources, e.g. extended memory and DPMI, while v2
only works through DPMI -- that's why no extender is needed.  Because
v1 gets its memory from different places, the amount it thinks is
free is different.  In particular, go32 manages the swapping to disk
itself, so it can use however much of your free disk space it likes,
without being restricted to what Windows is willing to sacrifice.

I am slightly confused though because I thought that when running in  
an environment like Windows go32 would just use DPMI.

> And 'go32-v2.exe' reported this:
> go32/v2 version 2.0 built Aug 12 1996 22:27:23
> Usage: go32 coff-image [args]
> Rename this to go32.exe only if you need a go32 that can run v2 binaries as
>  well as v1 binaries (old makefiles).  Put ahead of the old go32 in your PATH
>  but do not delete your old go32 - leave it in the PATH after this one.
> Set GO32_V2_DEBUG=y in the environment to get verbose output.
> 
> DPMI memory available: 12195 Kb
> DPMI swap space available: 1253 Kb

Did you adjust the DPMI memory provision in your DOS box settings?
Set it to 65535 and you should get more swap space.  Under djgpp v2
the amount of memory you get is entirely up to whatever DPMI server
you use.  On my system, in Windows 98 the two numbers add up to just
over 65000, which is what you would expect.

-- 
george DOT foot AT merton DOT oxford DOT ac DOT uk