PHP: return life of current session

Question

I am looking for a way to check on the life of a php session, and return the number of seconds a session has been "alive".

Is there a php function that I am missing out on?

Answer 1

You could simply store the timestamp on which the session was created in the session

Answer 2

You could store the time when the session has been initialized and return that value:

session_start();
if (!isset($_SESSION['CREATED'])) {
    $_SESSION['CREATED'] = time();
}

And for retrieving that information from an arbitrary session:

function getSessionLifetime($sid)
{
    $oldSid = session_id();
    if ($oldSid) {
        session_write_close();
    }
    session_id($sid);
    session_start();
    if (!isset($_SESSION['CREATED'])) {
        return false;
    }
    $created = $_SESSION['CREATED'];
    session_write_close();
    if ($oldSid) {
        session_id($oldSid);
        session_start();
    }
    return time() - $created;
}

Answer 3

I think there are two options neither are great but here they are.

1) If you have access to the file system you can check the creation timestamp on the session file.

2) Store the creation time in the session e.g.

session_start();
if( ! isset($_SESSION['generated'])) {
    $_SESSION['generated'] = time();
}