private static function getStartIp($RecNo) { $offset = self::$FirstStartIp + $RecNo * 7; fseek(self::$fp, $offset, SEEK_SET); $buf = fread(self::$fp, 7); self::$EndIpOff = ord($buf[4]) + ord($buf[5]) * 256 + ord($buf[6]) * 256 * 256; self::$StartIp = ord($buf[0]) + ord($buf[1]) * 256 + ord($buf[2]) * 256 * 256 + ord($buf[3]) * 256 * 256 * 256; return self::$StartIp; }