Caps Lock as Escape and Control revisited

As I’ve said before, my Caps Lock key serves as both my Left Control key (if I hold it), and my Escape key (if I tap it).

This configuration has a bug: occasionally entering Esc when I want an empty Left Ctrl. Essentially, when I hold down on the key and then let go without tapping any other key, the expected behaviour is that it should behave like tapping a Left Ctrl. The actual behaviour is that of tapping Esc, which is not the greatest key to accidentally tap.

Using Interception Tools’ Dual function keys

I’ve talked about the plugin in the post about trying to setup home row mods.

Install interception-tools and dual function keys. The installation process is available at the links; for Arch systems you can run sudo pacman -Syu interception-tools interception-dual-function-keys.

Then, configuration. Setup the following job in /etc/interception/udevmon.yaml:

- JOB: "intercept -g $DEVNODE | dual-function-keys -c path_to_config.yaml | uinput -d $DEVNODE"
  DEVICE:
    EVENTS:
      EV_KEY: [KEY_CAPSLOCK, KEY_ESC]

The config can be setup wherever is appropriate.

TIMING:
    - TAP_MILLISEC: 200
    - DOUBLE_TAP_MILLISEC: 0
MAPPINGS:
    - KEY: KEY_CAPSLOCK
      TAP: KEY_ESC
      HOLD: KEY_LEFTCTRL
    - KEY: KEY_ESC
      TAP: KEY_ESC
      HOLD: KEY_CAPSLOCK

Caveat with multiple configs

Generally, caveats as mentioned in the home row mods post apply. The key details are to ensure that

1. The udev file should be stored in /etc/interception/udevmon.yaml
2. Not more than one config can be used. If you want other key replacements like home row mods, the udev will remain as is and the yaml config will be:

TIMING:
  ...
MAPPINGS:
  # Enter your other mappings
  - KEY: KEY_CAPSLOCK
    ...

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