sig
val seek_out : Pervasives.out_channel -> int64 -> unit
val pos_out : Pervasives.out_channel -> int64
val out_channel_length : Pervasives.out_channel -> int64
val seek_in : Pervasives.in_channel -> int64 -> unit
val pos_in : Pervasives.in_channel -> int64
val in_channel_length : Pervasives.in_channel -> int64
end