Date: Thu, 6 Apr 1995 15:55:34 -0400 (EDT)
From: Chris Tate <FIXER AT FAXCSL DOT DCRT DOT NIH DOT GOV>
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: DPMI-safe screen access

I've got a program (not written by me) that writes to a text screen by building
temporary buffers, then using bcopy() to blast the data to ScreenPrimary. 
Needless to say, this crashes under DPMI (most notably in a DOS box under
Windows).

Unfortunately, I myself am not familiar with the ins and outs of using the
DPMI-safe dosmemput() or <farptr.h> routines, and I'd appreciate any advice
that people might offer me.

Just how would I go about expressing a text-screen blit as either a dosmemput()
to the right place, or something using the <farptr.h> routines, or some other
such approach that works under DPMI?  From the FAQ, I'm pretty sure that I'm
going to want to use movedata(), but I'm afraid I need some concrete examples
(I'm not at all used to an architecture that doesn't let you just treat *all*
of memory as one big flat space... :-/ )

-- Chris Tate
   fixer AT faxcsl DOT dcrt DOT nih DOT gov
   <http://world.std.com/~ctate/>