title: Check if there is a session without using session_start()
body: <p>I want to check if a person has an active session and redirect them to another page when they have one. However, I do not want to use <strong>session_start()</strong>, as that will place a cookie on the persons PC (I do not want to place cookies on peoples' PC when they're not logged in). Is there a way to check for an existing session, without placing a cookie on their PC?</p>