Date: Sun, 26 Dec 1999 09:35:13 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Valkir <jfd50 AT videotron DOT ca>
cc: djgpp AT delorie DOT com
Subject: Re: djgpp strangeness
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On Thu, 23 Dec 1999, Valkir wrote:

> > >  Video=Vesa.InitVesa();
> > >
> > > //////cDesktop Desktop;
> > >  for(x=0;x<800;x++)
> > >  for(y=0;y<2400;y++)
> > >  *(Buffer+x+y*800)=x;
> > >  memcpy(Video,Buffer,1920000);
> >
> > What kind of pointer/address does Vesa.InitVesa() return?
> >
> > If it is a real-mode pointer, you cannot use memcpy with it; see section
> > 18.2 of the FAQ for the details.
> 
> Vesa.InitVesa() return the linear frame buffer address for the vesa card.

Yes, but what kind of address is that?

DJGPP programs can use only protected-mode addresses that are offsets
relative to the program's DS selector's base address.  Anything else
needs special techniques to access without triggering a protection
violation.