else if(strcmp(argv[i], "-l") == 0) {
check_opt(argc, argv, i, 1, "<maximum number of lines>");
nb_lines_max = atoi(argv[i+1]);
else if(strcmp(argv[i], "-l") == 0) {
check_opt(argc, argv, i, 1, "<maximum number of lines>");
nb_lines_max = atoi(argv[i+1]);