strtodnum
del = strtodnum(buf, 0, UINT32_MAX / 1000000, &errstr);
delay = strtodnum(optarg, 0, UINT32_MAX / 1000000,
del = strtodnum(argv[0], 0, UINT32_MAX / 1000000, &errstr);
delay = strtodnum(argv[1], 0, UINT32_MAX / 1000000, &errstr);
double strtodnum(const char *, double, double, const char **);