From:	Charles Sandmann <sandmann AT praline DOT no DOT NeoSoft DOT com>
Subject:	Re: RM functions with DJGPP
To:	nigel AT algor DOT co DOT uk (Nigel Stephens)
Date:	Thu, 18 May 1995 14:09:41 -0500 (CDT)
Cc:	djgpp AT sun DOT soe DOT clarkson DOT edu

> Can you clarify this?  Under GO32 v1.x I believe that it was necessary
> to install both a protected-mode handler AND a real-mode handler, to
> ensure that interrupts weren't missed when GO32 switched to real-mode
> to call DOS/BIOS.

Correct when *NOT* using DPMI.  When using DPMI V1.x acts like V2.

> Is it true that a program using GO32 v2 (or any other "real" DPMI
> provider) runs totally in protected mode, using V86 mode to access
> DOS/BIOS functions, and that a real-mode handler is no longer
> absolutely required.

It is not necessary to write or install RM HW interrupt handler under 
DPMI (in V1.x or under V2).

V86 is not necessarily the mode for RM functions.  If an EMM manager is not
installed, CWSDPMI will change back to real mode (not V86 mode) to 
perform RM services (just like GO32 does now).

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