]> Annotation Glossary A allow-none NULL is ok, both for passing and for returning. E element-type Generics and defining elements of containers and arrays. T transfer container Free data container after the code is done. I in Parameter for input. Default is transfer none. T transfer full Free data after the code is done. C closure This parameter is a 'user_data', for callbacks; many bindings can pass NULL here. T transfer none Don't free data after the code is done.