Another SQL-newbie UDF question: qualifying with a library passed as a variable

[James Lampert <jamesl@xxxxxxxxxxxxxxxxx>]

Situation: I have a UDF that, because it's using unqualified filenames 
on SELECTs, can get confused about where to go for its data, if the 
library list is the list bit funky.

But the target library is not known at creation time.

I'd like to pass the library as a parameter. But is there a way to 
qualify the filename on a SELECT, using a variable (in this case, a 
parameter) as the library name?

--
JHHL