<?
session_cache_expire (30);

session_start();

function users() {
   $count = 0;

   $suksess = opendir(session_save_path());
   if ($suksess == false) return -1;

   while (($file = readdir($suksess)) != false) {
       if (ereg("^sess", $file)) $count++;
   }
   closedir($suksess);
   return $count;
}

echo "Users online: " . users() . "<br>";

?>