For day to day usage it is desirable to have the system automatically run liquidctl and configure each device by itself.
The first step is to create a script with all necessary calls to liquidctl. It can be written in any
language, but for simplicity I stick with a simple Bash script: liquidcfg.
The system then has to be configured to automatically start that script; most likely, you will want it to run at every boot.
How to do this will depend on the OS (and maybe distribution) you use. Personally, I run Arch Linux and, these days, Systemd is ubiquitous on most Linux distributions. I will assume you are running Systemd as well, but if this is not the case, check your distribution's documentation for how to configure programs to start at every boot.
With Systemd, the most straightforward setup is to add a new system
service. For my Bash
script, a Type=simple service is sufficient: liquidcfg.service. This file
is also called a unit file.
While communication with USB devices is usually restricted to users with root privileges, this is not an issue here because, by default, system services already run as the root user.
Unit files for system services should be installed inside /etc/systemd/system. It is also
necessary to run systemctl daemon-reload every time a change is been made to them.
The configuration script itself has fewer restrictions, and I like to have it inside
/usr/local/bin. I also use a simple Makefile to automate my installation
procedure.
Once you have created and installed your own script and service files, you can test them by starting the service.
# systemctl start liquidcfg
You can then use liquidctl, systemctl and journalctl to check if everything is working as it should.
# systemctl status liquidcfg -n 99
# journalctl -u liquidcfg
# liquidctl status
If necessary, you can also start the script manually, which will be easier to debug.
Finally, once you are happy with the results, enable the service to have it start automatically.
# systemctl enable liquidcfg
This folder also includes liquiddyncfg (and associated service and timer files), which I use to
dynamically configure my cooler and case lights throughout the day.
This is similar to the boot-time setup, except that a timer is used to have it run at period intervals.
For more information see: Trick: changing cooler and case lighting according to time of day (Linux&macOS) gn r/NZXT.