if($host === NULL || strlen($host) == 0) $host = "$";
if($ip === NULL || strlen($ip) == 0) $ip = "$";
if($mode === NULL || strlen($mode) == 0) $mode = "$";
if($host === NULL || strlen($host) == 0) $host = "$";
if($ip === NULL || strlen($ip) == 0) $ip = "$";
if($mode === NULL || strlen($mode) == 0) $mode = "$";