poliva/lightum — pull request #39 by SukkoPera (2014-11-14 00:18:39+00:00)
Title: Try to autodetect systemd and only use it if present.

On Slackware systemd is not available, so always behave as if -U was specified.

Also try to autodetect availability of systemd during make, and behave accordingly. This part should be tested on a system with systemd, as I'm not sure it works correctly.