Advice on writing Daemon in PHP/CI or ?

An AJAX request is (roughly) equivalent to spawning a new process on the server. Because CI is already in place it seems to me that using it would greatly shorten the development time and still be reasonably lightweight/efficient. From my point of view (as an old C programmer) writing a daemon would be a lot more effort than writing a controller and model combo to respond to an ajax request.

Another idea (possibly nearly as development intensive as a daemon in C) would be to use Node.js to process javascript on the server side. Node has a built-in HTTP module that listens to server ports and gives a response back to the client. It should be lighter weight and faster than apache/PHP and easier than writing a daemon.