opterr = 0; /* don't want writing to stderr */ while ( (i = getopt(argc, argv, "hp:c:e:")) != -1) { switch (i) { /* * Handling options */ case 'h': /* help option */ printf("Wrong -h option use\n"); usage(); return -1; break; case 'c': /* take wait time for children */ wait_child = strtol(optarg, NULL, 10); /* convert input */ break; case 'p': /* take wait time for children */ wait_parent = strtol(optarg, NULL, 10); /* convert input */ break; case 'e': /* take wait before parent exit */ wait_end = strtol(optarg, NULL, 10); /* convert input */ break; case '?': /* unrecognized options */ printf("Unrecognized options -%c\n",optopt); usage(); default: /* should not reached */ usage(); } } debug("Optind %d, argc %d\n",optind,argc);