Trying to avoid possible mistakes I'd like to define and use variables to be used withing the systemd
unit file itself, i.e.: not for the command executed.
For example consider this (invalid) unit:
[Unit]
CONFIG=/etc/some_dir/%i.conf
AssertPathExists=$CONFIG
#...
[Service]
EnvironmentFile=$CONFIG
# ...
So I want to define variable CONFIG
and use it for several unit directives.
Is that possible?