How to kill a session after logging out using php

Question

I have seen the following question and tried to adapt part of the answer but to no luck: \'How can i disable the back browser button after user press logout and destroy session?

Answer 1

As for headers, here are the ones from a web server I regularly use after a search:

Cache-Control: private, pre-check=0, post-check=0, max-age=0
Expires: 0
Pragma: no-cache

Pressing the back button after clicking a link from the results page displays an error message in Firefox. The only notable difference I see is Expire: 0.