From: sandmann AT clio DOT rice DOT edu (Charles W. Sandmann)
Subject: system() without swapping
To: djgpp AT sun DOT soe DOT clarkson DOT edu (djgpp)
Date: Wed, 19 May 1993 09:48:23 -0600 (CDT)

> From: Peter Geissler <pgeiss AT dali DOT uphys DOT uni-heidelberg DOT de>
> Subject: system() without swapping
> 
> Is there a possibility to prevent go32
> from swapping out complete to disk
> whenever a system() call is made ?
> I have to do system calls very often
> during the protected mode program is
> running, so that swapping becomes
> to time consuming. Perhaps it is
> possible to tell go32 to keep some
> amount of memory free for system
> calls instead of swapping ???
> (Im using go32 1.08)
> 
> Thanks for any suggestinons
> 
> Peter Geissler
> 
> pgeiss AT dali DOT uphys DOT uni-heidelberg DOT de

Some of the memory must be swapped to disk (page tables, etc) which are in
low memory.  Other parts could potentially be kept in memory, but you are
asking for problems if you try to run other images which want to do anything
except low memory access.  If you just want to system() "dir" and such 
type calls, there is code in the Japanese old GO32 version which minimizes
the amount of memory swapped.  I did not test it, but it looks like it opens
a can of worms.  The structure of memory calls have changed since then, so
some amount of hacking would be required to try and revive this feature.