From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: CWSDPMI under DOSEMU under Linux doesn't work.
Date:	Wed, 13 Oct 1999 11:59:47 +0200
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On Tue, 12 Oct 1999, Damian Yerrick wrote:

> I brought some DJGPP-built programs to my friend's
> Linux PC and tried them under FreeDOS on DOSEMU.
> They wouldn't run, even though I also brought along and
> unzipped CWSDPMI.

DOSEmu has its own DPMI server, so you shouldn't need CWSDPMI and you
shouldn't even try to use CWSDPMI.

If you load CWSDPMI manually *before* running DJGPP programs, don't:
it won't work, exactly like it doesn't on Windows.

If DJGPP programs run under DOSEmu claim there's no DPMI and ask for
csdpmi*b.zip, it probably means that DOSEmu's own DPMI services are
somehow disabled.  Either the DOSEmu docs or section 3.4 of the DJGPP
FAQ might help here.

> Error message when I started my program:
>
> Protected mode not accessible

This means that CWSDPMI tried switching the CPU into protected mode,
and that failed.  It's no surprise it fails on Linux: the CPU is
already in protected mode, so Linux doesn't allow to fiddle with the
PE flag in the CR0 register, which is what CWSDPMI does to enter PM.
The only way to go is to use the DOSEmu's built-in DPMI services.

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