let output_lines oc ic =
  let limit = 8000 in
  let rec rd_lines oc ic n =
    match (Stdio.In_channel.input_line ic, n) with
    | Some _, n when n = limit -> n
    | None, _ -> n
    | Some l, n ->
        Printf.fprintf oc "%s\n" l;
        rd_lines oc ic (n + 1)
  in
  rd_lines oc ic 0