Where is RSS/XML file? Can't find it on my server

I'm rebuilding one of my sites as a Drupal site and we want to generate a JavaScript newswire as we'd done on the previous one. Presumably the simplest thing to do is write a script (most likely in Perl) that reads the RSS/XML file automatically generated by Drupal - but where is it?

The site is here: http://en.iuf.org/

The XML for it is http://en.iuf.org/?q=rss.xml

But that's not a file name, is it? Where would I find it? I can't find that file anywhere on my server and I need to find it in order to read it and create the JavaScript based on it.

Thanks very much!