What is the best way to test for a font existence

[Olivier Galibert]

I have ~100 font names for which I want to test whether the X server
knows them.  The application (XEmacs) for now loads the font and
releases it later.  That works, but is rather slow (almost 3 seconds
added to startup time...), especially since we lazy-load the fonts as
needed afterwards.  What would be the best way to do that test,
especially since I can probably reasonably do a "font names to test"
list at compile time?

  OG.