Re: scrollback

Jon M. Taylor (
Sun, 27 Oct 1996 11:44:01 -0800 (PST)

On Sun, 27 Oct 1996, Harald Koenig wrote:

> > The recent traffic said that the screen gets scrolled by adjusting the
> > VGA's 'start of display memory' register, and that the kernel has no
> > clue as to what's scrollback and what's garbage.
> there are a few graphics cards/chips (at least DEC TGA, and I think monochrome
> cards like Hercules too) where the kernel (card?) doesn't support
> text scrolling yet. at least for them having a generic software method
> to scroll text VCs would be a *big* benefit. having this software method,
> one could define the scroll buffers as large as needed (and vice versa;).
> but keep in mind that this all goes into non-paged kernel memory and
> having 8 VCs with 1000 * 132 character lines is another MEGAbyte you're loosing...

Why not swap it to unused video card RAM? Of course, this would
require that the kernel know even more about video card specific
internals, which I don't think it does right now. Bummer, eh? Of
course, you *could* always use the GGI....