linux keyboard: how remap euro key from sequence ALT 0128 to PgUp?

Question

I have laptop Acer Aspire E1-772G and it have Euro key near cursor keys. I do not use Euro and moreover it is implemented so pressing it generate sequence ALT 0 1 2 8

# showkey -k
kb mode was ?UNKNOWN?
[ if you are trying this under X, it might not work
since the X server is also reading /dev/console ]

press any key (program terminates 10s after last keypress)...
keycode  28 release
^[0^[1^[2^[8keycode  56 press
keycode  82 press
keycode  82 release
keycode  79 press
keycode  79 release
keycode  80 press
keycode  80 release
keycode  72 press
keycode  72 release
keycode  56 release

This does a lot of problems, as I press it often by mistake. In mc it terminates it, it searches in history and so on

I would like to remap it to PgUp, to behave as expected from block of cursor keys, but i cannot find, where it is defined, or how to remap it. Can somebody help me?

I am using Gentoo with fluxbox and uxrvt as terminal.

PS: showkey shows the same even without X, but pressing the key just makes a box character (i suppose bad printed euro)

PSS: why it is not duplicate:

• I have the problem without xbindkeys running

• I have the problem even without X running

• my problem is opposite - how to stop a key from sending sequencies of codes, not how to send such sequencies - and the solution (run program to send sequence) does not help to "eat" the sequence, nor I can STOP using mentioned program, as it is not running already and the xmacroplay is not even present on my laptop

Answer 1

Given that ALT0128 is a Microsoft thing (to input characters on Windows using decimal code points in Microsoft character sets), I suspect it's done in hardware/firmware, not the (Linux-based) OS.

Probably all Linux sees is exactly the same thing it would see if you had pressed: keydown alt key 0 key 1 key 2 key 8 keyup alt.

To confirm that, you could run:

watch -d -n 0.2 cat /proc/interrupts

And compare what happens when you type A with €.

You should see some number increasing by two for A, and if it increases by 10 for €, then there's probably not much you can do at the OS level.

You could check with Acer if there's a way to reprogram the keyboard, or you could physically disconnect, break or glue or tape that key.

While I don't think there's much you can do at the OS or even X11 level, with GNU screen, you could bind the sequence of characters that the terminal would send upon that series of events to some action, like inserting the sequence of characters normally generated upon PageUP (in ~/.screenrc):

bindkey \0330\0331\0332\0338 stuff "\033[2~"

Then that would at least for terminal applications that you run within screen.