From:	"Alexei A. Frounze" <see_below AT the_messasge_body DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: far pointers
Date:	Sat, 10 Jun 2000 18:17:59 +0400
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To:	djgpp AT delorie DOT com
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Nate Eldredge wrote:
> 
> "Alexei A. Frounze" <see_below AT the_message_body DOT com> writes:
> 
> > WOW! Never heard DJGPP has nothing about V86... It would be impossible to
> > have (let's say) a disk I/O in DJGPP under DOS without V86. Sure V86 is
> > unnoticable for a user unless he is running into problems with VESA, IPX
> > stuff, etc etc and he starts to think of DPMI, PMode and V86 in order to
> > solve a task.
> 
> AFAIK, this is not true.  If you boot DOS without himem.sys or other
> memory manager, then run a DJGPP program using cwsdpmi, you can do
> disk I/O and everything else without ever entering V86 mode.  You just
> go backa and forth between protected and real modes.

You're wrong. 
1. HIMEM.SYS has nothing about V86. It just allows to access extended ram
(above 1MB mark).
2. CWSDPMI as a DOS extender (DPMI host or whatever you like to call it)
passes all the called DOS functions from PMode program to V86 task in order
to be handled by BIOS, IO.SYS, MSDOS.SYS, etc. None of good DOS extenders
switches back to real mode in order to service BIOS or DOS function.

bye.
Alexei A. Frounze
-----------------------------------------
E-mail:   alexfru [AT] chat [DOT] ru
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