+ if (opt == -1)
+ break;
+ switch (opt) {
+ case 't':
+ default_mtime = strtol(optarg, &invalid, 10);
+ if (!*optarg || *invalid) {
+ fprintf(stderr, "Invalid timestamp: %s\n",
+ optarg);
+ usage(argv[0]);
+ exit(1);
+ }
+ break;
+ case 'h':
+ case '?':
+ usage(argv[0]);
+ exit(opt == 'h' ? 0 : 1);
+ }
+ }
+
+ if (argc - optind != 1) {