[AUCTeX] biber does not produce bll file when called from emacs/AucTeX

[Rainer Thiel]

I recently switched to Emacs 26.1.  Now biber fails to make a bbl-file
when called from Emacs/AucTeX.  Everything works fine when I call

biber document

or

biber document.bcf

from the command line.  biber definitely is in the path, in fact I get
the message it was run successfully when called from Emacs.

Calling biber from Emacs used to work fine before.  My
TeX-command-list includes ("Biber" "biber %s.bcf" TeX-run-BibTeX nil t
:help "Run Biber").

Can someone please point me to what to do to be able to call biber
from Emacs/AucTeX again?

Many thanks in advance

Rainer

-- 
Prof. Dr. Rainer Thiel
Institut für Altertumswissenschaften
07737 Jena, Germany (EU)
address@hidden