usr.bin/getopt/getopt.c

#include <stdio.h>

main(argc, argv)
int argc;
char *argv[];
{
        extern int optind;
        extern char *optarg;
        int c;
        int status = 0;

        optind = 2;     /* Past the program name and the option letters. */
        while ((c = getopt(argc, argv, argv[1])) != EOF)
                switch (c) {
                case '?':
                        status = 1;     /* getopt routine gave message */
                        break;
                default:
                        if (optarg != NULL)
                                printf(" -%c %s", c, optarg);
                        else
                                printf(" -%c", c);
                        break;
                }
        printf(" --");
        for (; optind < argc; optind++)
                printf(" %s", argv[optind]);
        printf("\n");
        exit(status);
}