Re: Console mapping problems? [I hear about these - I wanna know!]

Martin Mares (
Wed, 10 Sep 1997 21:40:39 +0200


> So where is console init signalled? (userspace? specific normal reset
> sequence?)


> Is it possible to make it locale-based (if userspace)?
> IMHO it SHOULD be per-user and changeable ONLY on explicit request... That
> make sense?

Per user has no sense. Per console has a better one.

> Perhaps a new console sequence to reset the fonts.... either that or only
> the font-set sequences be able to reset the font.


> Uhmm... Loading/unloading fonts is ioctl, right? <sigh> - this makes it
> REALLY hard to emulate console under, say, X (I _REALLY_ don't like
> Xterm's keyboard/display/font mapping).

Yes, it's hard to emulate, but I know of no better way how to do it.

> I think the latin-1 centeredness is from having 4 pages of maps: (AFAIK)
> 1 - default latin-1
> 2 - graphical mapping
> 3 - IBM-PC mapping (for hysterical raisons :)
> 4 - userspace font

Yes. The IBM-PC mapping is not for HR only, it's currently the only way how to
extend the VT100 graphics to something more usable.

And also

5 - UTF8.

> Hmm - I'm not all that sure on how these interact though...
> [grabbing from 'console' source]
> VGA/text can handle up to 512 characters (some can handle more though -

Yes, but at the expense of having only 8 background colors.

> eg. Trident-8900 can handle 2048 characters AFAIK)
> The source itself prolly shouldn't be so latin-1 centric (though having
> ASCII as the only character set in the kernel would IMHO be a good idea -
> and I mean for all kernel messages et al - that is until the kernel
> supports more than textmode <sigh>)

The kernel should surely use only ASCII for its messages and the Latin-1
set should be only a default setting of the translation tables, but they
must be fully reloadable by user programs.

Have a nice fortnight

Martin `MJ' Mares   <>
Faculty of Math and Physics, Charles University, Prague, Czech Rep., Earth
"DEC = Delay in Error Correction"