For a long time this program was called qdoc. Because Trolltech might want to release its qdoc, it seemed sensible to rename this before release. A simple matter - just step along to the next letter, I thought. But then there turned out to be something called rdoc already. And two programs called sdoc. tdoc was taken too. From a few quick google searches, it seems that there's more than 26 programs like udoc.
You can understand why I considered naming this ditty fdoc.