Connects a GCallback function to a signal for a particular object.
The handler will be called before the default handler of the signal.
See [memory management of signal handlers][signal-memory-management] for details on how to handle the return value and memory management of data.
a string of the form "signal-name::detail".
the GCallback to connect.
data to pass to cHandler calls.
the handler ID, of type gulong (always greater than 0 for successful connections)
Connects a GCallback function to a signal for a particular object.
The handler will be called before the default handler of the signal.
See [memory management of signal handlers][signal-memory-management] for details on how to handle the return value and memory management of data.