I just found out go-systemd is actually polling :/

https://github.com/coreos/go-systemd/blob/13f092667e1fd20c642578aa92f20f357e3d60cd/dbus/subscription_set.go#L36

If someone wants to fix this, I know at least #mgmtconfig folks would appreciate it!

https://github.com/coreos/go-systemd/issues/377

go-systemd/dbus/subscription_set.go at 13f092667e1fd20c642578aa92f20f357e3d60cd · coreos/go-systemd

Go bindings to systemd socket activation, journal, D-Bus, and unit files - coreos/go-systemd

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