finding user latency

hi guys
so i found out the code to get users ip and resolve the ip to a dns also

now does some one have a script to find out user latency?
anyone

latency or rtt

-----------
to get some one Ip address
and resolve the dns name i use this

if (getenv('HTTP_CLIENT_IP')) {
$IP = getenv('HTTP_CLIENT_IP');
}
elseif (getenv('HTTP_X_FORWARDED_FOR')) {
$IP = getenv('HTTP_X_FORWARDED_FOR');
}
elseif (getenv('HTTP_X_FORWARDED')) {
$IP = getenv('HTTP_X_FORWARDED');
}
elseif (getenv('HTTP_FORWARDED_FOR')) {
$IP = getenv('HTTP_FORWARDED_FOR');
}
elseif (getenv('HTTP_FORWARDED')) {
$IP = getenv('HTTP_FORWARDED');
}
else {
$IP = $_SERVER['REMOTE_ADDR'];
}

$hostname = gethostbyaddr($_SERVER['REMOTE_ADDR']);

echo $_SERVER['REMOTE_ADDR'];

echo $hostname;


echo $IP;

You could theoretically ping them and get the response time however many people have incoming ICMP trafic disabled.

~Phil~

do you have a code to ping them and get the time back
response ?