private static function init()
{
if (self::$fp === NULL) {
self::$ip = new self();
self::$fp = fopen(__DIR__ . '/17monipdb.dat', 'rb');
if (self::$fp === FALSE) {
throw new Exception('Invalid 17monipdb.dat file!');
}
self::$offset = unpack('Nlen', fread(self::$fp, 4));
if (self::$offset['len'] < 4) {
throw new Exception('Invalid 17monipdb.dat file!');
}
self::$index = fread(self::$fp, self::$offset['len'] - 4);
}
}