("--odir", Arg.String (fun s -> dir_output := s), ": set output directory");
("--oformat", Arg.String (fun s -> format_output := s), ": set output format");
("--obasename", Arg.String (fun s -> basename_output := s), ": set output basename");
("--odir", Arg.String (fun s -> dir_output := s), ": set output directory");
("--oformat", Arg.String (fun s -> format_output := s), ": set output format");
("--obasename", Arg.String (fun s -> basename_output := s), ": set output basename");