I am building a system that has urls like app.com/login and app.com/dothing but it will also have app.com/xOldP. The web application is build using the latest version of Code Igniter and I was wondering if there was a way to add a check in, that if the url is a controller then do that and finish, but if not, do something else (which will check the url and if its not real 404, which I can do).

I was wondering how annoying this would be :/ Some sample code or links would be great!