c_g_bus_watch_name_on_connection

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
uint function(GDBusConnection* connection, const(char)* name, GBusNameWatcherFlags flags, GBusNameAppearedCallback nameAppearedHandler, GBusNameVanishedCallback nameVanishedHandler, void* userData, GDestroyNotify userDataFreeFunc) c_g_bus_watch_name_on_connection;

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