Re: Ignoring a key event completely

[Kevin Rodgers]

Michael Schutte wrote:
> Hi everybody,
>
> The XKB layout I’m using [1] defines an additional modifier, the
> Navigation key.  Whenever I press it, Emacs responds by beeping and
> printing “<key-17> is undefined”.  I can suppress this by
> global-set-keying it to 'ignore, but this does not turn it off
> completely.  In particular:
>
>  * Hitting the key still interrupts Isearch, which is very annoying.
>  * M-Nav, C-Nav and C-M-Nav also need to be 'ignored, which does not
>    seem very elegant to me.
>  * Messages appearing in the echo area are nuked when I press Nav (this
>    is minor, of course, but you get the idea).
>
> So, I’m looking for a way to make Emacs completely forget about the key,
> to make it as no-oppy as Shift, Ctrl, etc., but I simply can’t find out
> how to do this on my own.  Could anyone give me a clue?
>
> [1] <https://neo.eigenheimstrasse.de/svn/linux/X/de>; grep for Mod4

I don't think I've ever been on a system that generates events like
<key-17>.  What does Emacs display after typing `a', then the Navigation
key, then `C-h l'?

In any case, it looks like the Navigation key is not a modifier key like
Shift, Control, etc.  So perhaps something like this will work:

(define-key special-event-map (kbd "<key-17>") 'ignore)

See the "Controlling Active Maps" and the "Special Events" nodes of the
Emacs Lisp manual.

--
Kevin Rodgers
Denver, Colorado, USA