pub unsafe extern "C" fn g_signal_new(
signal_name: *const c_char,
itype: GType,
signal_flags: GSignalFlags,
class_offset: c_uint,
accumulator: GSignalAccumulator,
accu_data: gpointer,
c_marshaller: GSignalCMarshaller,
return_type: GType,
n_params: c_uint,
...
) -> c_uint