[tex-k] How to expand kpathsea list of file types?

[Karl Berry]

    I'd like to add biblatex style files (i.e. *.cbx and *.bbx) 

They're in the TEXINPUTS path.  Look them up as TeX files and you will
find them.

It has to be that way because, as you know, it's TeX that reads them.

    cls, sty

It seems to me you should be able to handle cbx/bbx in the same way as
cls and sty.  There are no separate paths for those either.

Best,
Karl