check.php

<?php
$users = split("\n", file_get_contents('friends.txt'));
$yes = 0;
$no = 0; 
foreach($users as $user)
{
    $xml = simplexml_load_string(file_get_contents('http://search.twitter.com/search.atom?q=from%3A'.$user));
    if($xml->entry)
    {
        $yes++;
        echo $user.": yes\n";
    }
    else
    {
        $no++;
        echo $user.": no\n";
    }
}
echo "yes: ".$yes."\n";
echo "no: ".$no."\n";
?>