[XeTeX] Checking if a font exists

[Akira Kakuto]

> >    Doesn't XeTeX implement \suppressfontnotfounderror that was added to
> > pdfTeX two or three years ago, precisely to deal with this kind of
> > problem?
> 
> To the best of my knowledge, it does. But an explicit \errmessage
> was given in the example code.

Thanks. There is a difference between
\suppressfontnotfounderror0
\font\xx="Foo Bar"
\xx test
\bye

and

\suppressfontnotfounderror1
\font\xx="Foo Bar"
\xx test
\bye

Best,
Akira