The interface/instance type that this signal can be emitted for.
The number of parameters that user callbacks take.
The individual parameter types for user callbacks, note that the effective callback signature is:
`return_type` callback (#gpointer data1,
[param_types param_names,]
gpointer data2);
The return type for user callbacks.
The signal flags as passed in to g_signal_new().
The signal id of the signal being queried, or 0 if the signal to be queried was unknown.
The signal name.
A structure holding in-depth information for a specific signal.
See also: g_signal_query()