Before getting deeper into the routing system, one matter needs to be clarified. In the examples given in the previous section, there is no mention of the front controller (index.php or frontend_dev.php) in the internal URIs. The front controller, not the elements of the application, decides the environment. So all the links must be environment-independent, and the front controller name can never appear in internal URIs.

There is no script name in the examples of generated URLs either. This is because generated URLs don't contain any script name in the production environment by default. The no_script_name parameter of the settings.yml file precisely controls the appearance of the front controller name in generated URLs. Set it to off, as shown in Listing 9-5, and the URLs output by the link helpers will mention the front controller script name in every link.