How to detect whether session_start() has been called in PHP?

Question

Possible Duplicate:
how do i check if session_start has been entered?

Is there such an API?

score 7 · Accepted Answer · answered Jan 04 '10 at 06:41

7

You can find out by calling the following code:

if(isset($_SESSION))
{
    //The session was started
}

answered Jan 04 '10 at 06:41

Sam Becker

3

Keep in mind that `session_write_close()` ends the session mechanism but doesn't destroy _SESSION. – VolkerK Jan 04 '10 at 08:27
This answer is not correct. As VolkerK points out, `$_SESSION` can still be set even though the session has been closed. And nothing prevents a user from declaring $_SESSION without starting a session. A better check would be: `if (session_id())` (For PHP versions < 5.4.0) or `if (session_status() != PHP_SESSION_NONE)` (For PHP versions >= 5.4.0) – Stefan Dec 15 '16 at 13:47
Also, you can call `session_start()` without ever setting $_SESSION. Your check will then tell you that `session_start()` was never called, which is incorrect. – Stefan Dec 15 '16 at 14:17

1 Answers1