the gobject.Closure to which the marshaller belongs
a gobject.Value to store the return value. May be NULL if the callback of closure doesn't return a value.
the instance on which the closure is invoked.
va_list of arguments to be passed to the closure.
additional data specified when registering the marshaller, see Closure.setMarshal and Closure.setMetaMarshal
the GType of each argument from args_list.
2.30
A generic GVaClosureMarshal function implemented via libffi.