val enum : (string * int64) list -> 'a Ctypes.typ -> unit
val structure : _ Ctypes.structure Ctypes.typ -> unit
val union : _ Ctypes.union Ctypes.typ -> unit
val typedef : _ Ctypes.typ -> string -> unit
val internal : ?runtime_lock:bool -> string -> ('a -> 'b) Ctypes.fn -> ('a -> 'b) -> unit