Detect if PHP session exists

Question

Facebook now offer subscriptions to users so you can get realtime updates on changes. If my app receives an update, I plan to store it in the database. I would also like to detect if their session exists. If it does then I could update the data in there too.

My session IDs are MD5(fb_id + secret) so I could easily edit their session. The question is how can I detect if the session exists.

Answer 1

I use a combined version:

if(session_id() == '' || !isset($_SESSION) || session_status() === PHP_SESSION_NONE) {
    // session isn't started
    session_start();
}