Re: utf-8 input under X11

[David Monniaux]

CONGRATULATIONS KENICHI-SAN !

[xterm.c]
> thus the byte sequence returned by XmbLookupString is not
> decoded.  But, in the for loop at line 10601, we have this
> code:
>
>                         for (i = 0; i < nbytes; i += len)
>                           {
>                             c = STRING_CHAR_AND_LENGTH (copy_bufptr + i,
>                                                         nbytes - i, len);
[replace it by:]
> if (nbytes == nchars)
>   c = copy_bufptr[i], len = 1;
> else
>   c = STRING_CHAR_AND_LENGTH (copy_bufptr + i, nbytes - i, len);

> Could you change the code as above, and try again without
> setting locale-coding-system to utf-8?

It just works, whether or not locale-coding-system is set to utf-8. I 
nevertheless have to use encoded-keyboard (which I don't have to use 
if I'm using ISO-8859-1 or KOI8 locales).

I guess that there remain some polishing touches :

1/ If running in an UTF-8 locale, Emacs should set automatically 
locale-coding-system to utf-8, as it does for ISO-8859-1 (it sets the 
variable to iso-latin-1).

2/ If locale-coding-system is utf-8, Emacs should decode keyboard 
input as utf-8 (this looks like it has something to do with the code 
around line 10573). I don't see why the user should have to do 
something special (like set-keyboard-coding-system) if using utf-8, 
but not if using koi8-r !

3/ The documentation for locale-coding-system should reflect this 
role, since the current documentation only talks of "system messages".

> >>  I now did experiments setting locale-coding-system to 'utf-8.
> >> The results are pretty much interesting. I don't have to
> >>  (set-keyboard-coding-system 'utf-8)
> >>  - <Multi_key o e> gives oe ligature (correct)
> >>  - <Multi_key O E> gives oe ligature (correct)
> >>  - <Multi_key E => gives the Euro sign (correct)
> >>  - AltGr-E abandons instead of giving the Euro sign
> >>  - the Russian characters give garbage

With your patch, it looks like everything works fine. I tried all the 
above key combinations, they all work fine.

-- 
David Monniaux            http://www.di.ens.fr/~monniaux
Laboratoire d'informatique de l'École Normale Supérieure,
Paris, France