c_g_dbus_connection_signal_subscribe

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)* sender, const(char)* interfaceName, const(char)* member, const(char)* objectPath, const(char)* arg0, GDBusSignalFlags flags, GDBusSignalCallback callback, void* userData, GDestroyNotify userDataFreeFunc) c_g_dbus_connection_signal_subscribe;

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