A pretty weird problem while accessing session outside of zen

I'm trying to access $_SESSION outside of zen, the purpose is to set a certain variable to see if js is enabled or not (the file is placed at zen root folder and called via ajax)

    require('includes/application_top.php');
    
    sleep(5);
    
    $_SESSION['javascript_enabled'] = true;
    
    exit();

You can notice I have to use sleep(5), otherwise the session is still set (when I print_r), but it's not stored at all (when you go to the next page)

I suspect we have a race condition here? It's weird since I thought php can not work that way.

I would assume it is because application_bottom.php is not included. That, in turn, would call session_close (or similar). My understanding is that that will trigger persisting the session.

mano

Thanks mano, i've been bashing my head against the wall about this for a long time.
If you ever in wgtn, I'll buy you a beer/coffee/preferred liquid refreshment.
Cheers
Dave T