access the last key pressed (magic key)

[TiDemieH]

I want to implement a key which changes its output based on the last key I pressed (a magic key), for example a key that repeats the last key I pressed. I would like to find which key I pressed last using Karabiner and not a separate keylogger.

Is there a way to use a karabiner keypress-activated shell scripts to either

1. receive keypresses from karabiner-grabber?
2. extract logged keypresses from somewhere else like Event-Viewer? (which already has UI logs but I don't know how to interact with that)
3. detect final output from karabiner's virtual keyboard?

All help is appreciated.

[tekezo]

Basically, there's no way to send key inputs outside of karabiner_grabber, and while there are exceptional methods using complex modifications, I wouldn't recommend them. Such approaches could allow other processes to capture keystrokes without permission.
I suggest considering whether it's possible to achieve your goal with complex modifications.