I\'m trying to do exactly the same thing as in my previous Python question, but in PHP. See my previous (answered) question
PHP script from previous question does someth
To the best of my knowledge, there isn't any way to run a second page (AJAX is the exception). As far as I know, PHP doesn't support multiple threads (please correct me if I'm wrong) and the 'single-thread' nature of the web seems to defeat it anyways.
I would rather be inclined to look at your specific application and find out why you need to have two separate pages run - and then re-engineer the process so it does not.
I'd be willing to bet that a re-engineer would end being less of a headache from a development standpoint, as well as a logic and implementation one.