From: Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: addressing question
Date: 13 Sep 2001 14:40:17 GMT
Organization: Aachen University of Technology (RWTH)
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To: djgpp AT delorie DOT com
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dima 3141596 <dima AT rts-ukraine DOT com> wrote:

>  Ok, I have GDT with 3 valid entries: code segment, data segment and
> data segment pointed to video RAM (0x0b8000).  Than I switch to PM

You cannot do that, in a DJGPP application.  You *are* in PM, all the
time, so there's nothing to switch away from, into PM.

> How can I make it in the DJGPP ?

Use far*() functions or dosmemput().  Or reinvent what they're doing,
using inline asm, if you really believe that gains you anything.

Those functions ware added to DJGPP for a reason, see?

> but djgpp has not  far* !!!

Right. And for a good reason, too.  It violates the most basic
assumptions the C programming language makes about how the host
computer works, causing all kinds of ill effects.

> I try functions described in the farptr.h. It's work but I want to
> use C POINTERS !!!

You may want to, but DJGPP does not and will not let you. A far
pointer (as found in 16bit DOS compilers, including Borland Turbo C)
*is* not a C pointer.  I may look like one, but it isn't.




-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.