ydotool
requires that ydotoold
be running in the background. Now to make this easier the developer ships a systemd
unit file with the project.
A systemd
unit file contains code to direct systemd
to handle a resource called a systemd service
. A service
can either
be : enabled
or disabled
. When enabled
it can be started or stopped.
This file invokes ydotoold
as a service and makes it run in the background so ydotool
itself can be used.
When you initially download the package the service is disabled by default. You can check this by running :