is it safe to use two contradictory ini_set in php?

Question

I have a website with two distinct scripts, one requires the session.use_cookies to be 0 and the other one to be 1. For now I just took care of the first one with ini_set like this:

ini_set('session.use_cookies','0');

but now I'm wondering if I set it to 1 on my second script and run then simultaneously (by two different users), will both settings be contained within their own script or will they stomp each other in undefined behavior?

Answer 1

To quote the manual:

The configuration option will keep this new value during the script's execution, and will be restored at the script's ending.

ini_set changes the configuration option for the runtime of current script, without interfering with any other scripts running at that time. There's no way to alter execution of another user's script by using ini_set, or virtually anything else for that matter.