argument list for the signal emission. The first element in the array is a #GValue for the instance the signal is being emitted on. The rest are any arguments to be passed to the signal.
the signal id
the detail
Location to store the return value of the signal emission. This must be provided if the specified signal returns a value, but may be ignored otherwise.
Emits a signal.
Note that g_signal_emitv() doesn't change @return_value if no handlers are connected, in contrast to g_signal_emit() and g_signal_emit_valist().