I want to be informed about all state changes of service units. I know there is the DBUS API which gives me signals for UnitNew and UnitRemoved, but the semantic is still unclear to me. Also the signals doesn't provide the informations I need.
I'm using go and tried the go-systemd lib from coreos. They provide a way to "subscribe" but it's in fact polling all the unit information available in the system. I do not want to do so every few milliseconds, just to get informed about statechanges.
I also tried the default org.freedesktop.DBus.Properties but I can not get this working.
Please help If you can, I'm out of ideas.