<?php
    session_start();
    if($_SESSION['name']=="")
        header("Location: index.php");
    else{
        $cookie_name = "userID";
        $cookie_value = $_SESSION['name'];
        setcookie($cookie_name, $cookie_value, time() + (86400 * 30), "/"); // 86400 = 1 giorno
    }
    if(isset($_COOKIE['userID'])){
        $_SESSION['name']=$_COOKIE['userID'];
    }
?>