c- parsing command line options with multiple arguments with getopt_long

Question

I am new to c programming using command line arguments so despite finding few simmilar posts I am still stuck on this problem.

I need to pass a command line option that have more than 1 argument, for example

./testProgram --command arg1 arg2 arg3

here is my code

 static struct option long_options[] = {
        {"rdonly",     required_argument, 0,   'a'},
        {"wronly",     required_argument, 0,   'b'},
        {"command",    required_argument, 0,   'c'},
        {"verbose",    no_argument,       0,   'd'},
        {0,0,0,0}
      };


 c=getopt_long(argc,argv, "", long_options, &option_index);

      if(c == -1)
        break;

      switch(c) {
      case 'a':
          rdonly(fd,optarg);
        break;

      case 'b':
        wronly(fd,optarg);
        break;

      case 'c':
        command(optind,optarg,argc,argv);
        break;

      case 'd':
        printf("its verbose\n");
        break;

      default:
        printf("WRONG OPTION\n");
      }
    }


//command function

int command(int optind, char *optarg, int argc, char* argv)
{

  printf("Its option command with argument %s\n",optarg);

        return 0;
}