args_parse function may have a bug

[zxxunkxzhx]

case ARGS_OPT_INTEGER:
if (opt_arg == NULL)
return ARGS_ERROR_REQUIRED_INTEGER_ARG;

*(long*) opt->value = _tcstol(opt_arg, &endptr, 0);

if (*endptr != '\0')  ////////////////////////////////// endptr point to the last non-digit char, it may NOT point to '\0'
  return ARGS_ERROR_REQUIRED_INTEGER_ARG;

if (opt_arg_was_used != NULL)
  *opt_arg_was_used = 1;

break;

[plusvic]

Exactly, endptr always point to the ending null-character (\0) if the input is all digits. If endptr points to something else is because the input contains some non-digit character. In such cases it returns ARGS_ERROR_REQUIRED_INTEGER_ARG. If the user enters something like 123x it doesn't take the 123 as a number and discard the x, it returns an error.