Subject: Re: Codeset support for wscons
To: None <>
From: Valeriy E. Ushakov <>
List: tech-kern
Date: 04/01/2002 17:49:04
On Mon, Apr 01, 2002 at 13:40:35 +0200, Juergen Hannken-Illjes wrote:

> With Lennart Augustsson addition of cyrillic keysymbols (which is totally
> wrong this way) we need a method to pass non-iso8851-1 keystrokes through
> wscons.
> I propose two ioctl's to get/set a codeset on a screen. The codesets map
> keysymbols to 8-bit characters.

I don't like the whole wscons/unicode business in its current shape.
It's absolutely undocumented and its design goals are not clear.  I
tried to brought up this question several times but got absolutely no

E.g. what are the clients of this kbd codeset API other than the
kernel itself?  Do you expect 1) several programs 2) working with raw
ws events 3) running simultaneously and 4) using different locales

The 1-4 above hold for X11, so in X11 the keysym design is justified.
But wscons is a terminal emulator, I just don't see any need for such
complexity of (de facto) internal interfaces.

Exisiting usage of unicode in wsfont stuff also seems to me like an
overkill.  First, note that wscons doesn't provide for multicharset
output, e.g. I cannot display a mixture of cyrillic and latin-1 text
on a single wsscreen, so I think it's not a big stretch to say that
wscons emulates something that is, conceptually, a terminal like vt220
with downloadable fonts.

Consider a real hardware vt220 with loadable fonts.  I can load a
koi8-r font or ISO8859-5 font or latin-N font and vt220 doesn't care,
it will just happily pass on G1 chars and let the user take care that
the loaded font matches his locale.  This is a very well understood
model that's been around for ages.

Now why this unicode stuff is in then?  From reading the source the
only usage I can see is to remap line drawing chars.  As long as I
don't use line drawing chars, I can load a koi8-r font into wscons
(w/out specifying any encoding, in fact lying to it that the font is
iso) and use it happily b/c the vt100 emulation in wscons is just like
a real vt, it doesn't give a damn about G1 chars, it just passes them
on and displays them in whatever font is loaded.

So for this simple terminal emulation why do we need a layer of
unnecessary complexity?  The problem with line drawing chars can be
solved without throwing all the unicode at it.

SY, Uwe
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