Check if telnet server is up

I need a (php hopefully) function to check to see if a telnet server is up, and I have no clue where to start looking.

Given an IP, it tries to connect to a telnet server, and returns true if the server is up.

If this is too difficult, return true if the IP is online.

If anyone knows the code or where I can find it, I'd appreciate it.

Use fsockopen() and try to connect to port 23 (the default telnet port). If it fails, then the server is not up.

Diego

thanks

this test code works ok if i have the server up, but if it's down i still get "server up" after a wait (timeout?)

<?
if(fsockopen("66.73.199.244", 23))
{
echo"server up";
}
else
{
echo"server down";
}
?>

what am i doing wrong?