+bool bus_has_subscriber(Manager *m);
+bool bus_connection_has_subscriber(Manager *m, DBusConnection *c);
+
+DBusMessage* bus_properties_changed_new(const char *path, const char *interface, const char *properties);
+
+#define BUS_CONNECTION_SUBSCRIBED(m, c) dbus_connection_get_data((c), (m)->subscribed_data_slot)
+#define BUS_PENDING_CALL_NAME(m, p) dbus_pending_call_get_data((p), (m)->name_data_slot)
+