From: Bob Kematick <kmatick AT binghamton DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DPMI for Dummies
Date: Sat, 04 Apr 1998 13:36:53 -0600
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John M. Aldrich wrote:

[snip]

> 
> Please also note that DJGPP malloc() rounds all memory requests up to
> the nearest power of 2, and Windows 95's DPMI host won't let you
> allocate any more than half of the remaining virtual memory in any
> single chunk.  So, calling malloc() with a request greater than or near
> to 32 MB is almost guaranteed to fail even though it looks like you have
> enough available memory.
> 
> If you don't like this behavior, run in DOS with cwsdpmi, which lets you
> use up to 256 MB of combined physical and virtual memory (up to 512 MB
> with revision 4).
> 

 Eliminate DPMI constraints , dump DJGPP , switch to Cygnus GNU-WIN32 ,
 build a true Win32 app that has access to all of Windows virtual
 memory space.  :-(

 The 64 Mb DPMI limit in a dos box is a modern day version of the 640k 
 limit.