#pragma clang diagnostic ignored "-Winvalid-pp-token"
#pragma clang diagnostic ignored "-Wdeprecated-writable-strings"
#include <stdio.h>  /* for printf */
#include <stdlib.h> /* for exit */
#include <getopt.h>

int main(int argc, char **argv) {
  int c;
  int digit_optind = 0;

  while (1) {
    int this_option_optind = optind ? optind : 1;
    int option_index = 0;
    static struct option long_options[] = {
        {"add", required_argument, 0, 0},
        {"append", no_argument, 0, 0},
        {"delete", required_argument, 0, 0},
        {"verbose", no_argument, 0, 0},
        {"create", required_argument, 0, 'c'},
        {"file", required_argument, 0, 0},
        {0, 0, 0, 0}};

    c = getopt_long(argc, argv, "abc:d:012", long_options, &option_index);
    if (c == -1) break;

    switch (c) {
      case 0:
        printf("option %s", long_options[option_index].name);
        if (optarg) printf(" with arg %s", optarg);
        printf("\n");
        break;

      case '0':
      case '1':
      case '2':
        if (digit_optind != 0 && digit_optind != this_option_optind)
          printf("digits occur in two different argv-elements.\n");
        digit_optind = this_option_optind;
        printf("option %c\n", c);
        break;

      case 'a':
        printf("option a\n");
        break;

      case 'b':
        printf("option b\n");
        break;

      case 'c':
        printf("option c with value '%s'\n", optarg);
        break;

      case 'd':
        printf("option d with value '%s'\n", optarg);
        break;

      case '?':
        break;

      default:
        printf("?? getopt returned character code 0%o ??\n", c);
    }
  }

  if (optind < argc) {
    printf("non-option ARGV-elements: ");
    while (optind < argc) printf("%s ", argv[optind++]);
    printf("\n");
  }

  exit(EXIT_SUCCESS);
}