How to install Interception Tools on Pop!_OS
What is Interception Tools?
It's a software that lives between the kernel and the X server. It processes the input events and can modify it.
Why is it useful?
You can modify the keyboard layout, or make the keyboard act like a mouse, or...
Why did I get interested in it?
Pressing Esc is hard. Pressing ctrl is hard. I use vim.
Why did I write this post?
Because I'm sure I will be coming back to this and the main developers apparently hate Ubuntu!
sudo apt install libudev-dev libyaml-cpp-dev libevdev-dev cmake
I also needed to install the boost libraries:
sudo apt install libboost-all-dev
Now, clone the Interception Tools repo, compile and install it:
git clone https://gitlab.com/interception/linux/tools
sudo make install
Now, install the Capslock to Escape plugin for it:
git clone https://gitlab.com/interception/linux/plugins/caps2esc
sudo make install
Now, we need to configure Interception Tools to use the caps2esc plugin:
sudo mkdir -p /etc/interception/udevmon.d/
sudo vim /etc/interception/udevmon.d/c2e.yaml
And copy the following in it:
- JOB: intercept -g $DEVNODE | caps2esc | uinput -d $DEVNODE
In this case I am referring to my exact keyboard. You can find your keyboard using:
ls /dev/input/by-id | grep kbd
My laptop keyboard was under:
ls /dev/input/by-path | grep kbd
That being said, it is probably possible to use a more general config like this:
- JOB: "intercept -g $DEVNODE | caps2esc | uinput -d $DEVNODE"
EV_KEY: [KEY_CAPSLOCK, KEY_ESC]
Now that the configuration is done we need to add udevmon to the services so that it starts with the system.
Open this file:
sudo vim /etc/systemd/system/udevmon.service
and copy the following in it:
ExecStart=/usr/bin/nice -n -20 /usr/local/bin/udevmon
Make sure that the address for `udevmon` is correct:
Make sure to enable this service:
sudo systemctl enable --now udevmon
Also make sure to add the user to all the groups that are relevant. (not sure which one is relevant):
sudo usermod -a -G sudo $USER
sudo gpasswd -a $USER input
usermod -a -G plugdev $USER
After a reboot, the Esc key acts like CapsLock key. And the CapsLock key acts like both the Esc key and the Ctrl key. If you tap the CapsLock key, it will register as Esc, and if you hold it down and press another key it will register it as Ctrl and perform a combination. So, for example CapsLock+C will copy, but tapping the CapsLock key, will be just an Esc event.