if (argc == 2) {

	while ((ch = getopt(argc, argv, "")) != -1)

		if ((p = realpath(argv[1], buf)) == NULL)

		switch(ch) {

			err(1, "%s", buf);

		case '?':

	} else

		default:

			usage();

		}

	argc -= optind;

	argv += optind;

	if (argc < 1)

	(void)printf("%s\n", p);

	do {

		if ((p = realpath(*argv, buf)) == NULL)

			err(1, "%s", *argv);

		else

			(void)printf("%s\n", p);

	} while (*++argv != NULL);

	(void)fprintf(stderr, "usage: realpath path\n");

	(void)fprintf(stderr, "usage: realpath path [...]\n");