bug#43830: keyboard layout handling incompatible with rest of the OS

[Eli Zaretskii <eliz@gnu.org>]

> From: Juri Linkov <juri@linkov.net>
> Cc: Eli Zaretskii <eliz@gnu.org>,  43830@debbugs.gnu.org
> Date: Sun, 01 Nov 2020 09:53:08 +0200
> 
> > The point is that the character is not enough, you need to know both
> > the character and the physical key (you cannot reconstruct the key
> > from the character alone). E.g. suppose I type 'й' in Russian layout.
> > If it is a self-inserting command, character 'й' should be added to the
> > active buffer. But if I'm typing a multikey binding, it should be
> > interpreted as 'q' (it's the same physical key), so that e.g. 'C-ч й' is
> > translated to 'C-x q'.
> 
> What is worse is that in a writable buffer, typing 'й' should insert
> this character untranslated, but in the same buffer when it's in
> read-only view mode, typing the same 'й' should translate it to 'q'
> and quit the buffer with the View-quit command.  When using reverse-im
> with local-function-key-map, the Help buffer says:
> 
>   q (translated from й) runs the command View-quit.
> 
> So the question is whether it's possible to do the same using
> XkbTranslateKeyCode?  The local-function-key-map is smart enough
> to not translate self-inserting keys.  Can code for XkbTranslateKeyCode
> use the same condition to detect self-inserting keys?

Why do you want XkbTranslateKeyCode to do this? why not the code in
keyboard.c that reads the event queue and invokes commands?  If we
make both the key and the character available to keyboard.c, it should
be able to figure out what is TRT in each situation, I think.