CTar::getLastNum

static function getLastNum($file)
{
	$file = self::getFirstName($file);

	if (!file_exists($file))
		return false;
	$f = fopen($file, 'rb');
	fseek($f, 12);
	if (fread($f, 2) == 'LN')
		$res = end(unpack('va',fread($f, 2)));
	else
		$res = false;
	fclose($f);
	return $res;
}