# Print text when bibliography is empty

With biblatex, I'm looking for a way to check if the bibliography is empty, and if so, print some custom text.

Something along the lines of this pseudocode:

\ifempty\thebibliography
[[ no references found ]]
\else
\printbibliography
\fi


I could not find any options in the biblatex documentation controlling the behavior on empty bibliographies. Did I overlook something? Is this at all possible?

EDIT: Here's a MWE with Ulrike's suggestion implemented:

\documentclass[twoside,a4paper,11pt]{report}

\usepackage{biblatex}
\makeatletter
\def\blx@warn@bibempty{[THIS TEXT PRINTS WHEN NO BIBLIOGRAPHY IS PRINTED]}
\makeatother

\begin{filecontents}{\jobname.bib}
@BOOK{hectic,
AUTHOR    = {Henry Hectic},
TITLE     = {How Horticulturalists Howl},
PUBLISHER = {Honorary Books: Henage},
YEAR      = {2000}
}
@BOOK{flutter,
AUTHOR    = {Frederick Flutter},
TITLE     = {Fraternising with Flowers},
PUBLISHER = {Frippery Pamphlets: Folkestone},
YEAR      = {1995}
}
\end{filecontents}

\begin{document}

% Comment back in to see the normal bibliography

\printbibliography

\end{document}

• biblatex warns you if the bib is empty. You could redefine the command used for the message \blx@warn@bibempty. – Ulrike Fischer Jul 31 '14 at 10:31
• @UlrikeFischer ... that's a bit beyond my abilities. Could you give a small example? – Rody Oldenhuis Jul 31 '14 at 10:34
• \makeatletter\def\blx@arn@bibempty{Try it out}\makeatother (put is somewhere behind \usepackage{biblatex} naturally) (untested as you didn't provide a complete document for a test). – Ulrike Fischer Jul 31 '14 at 10:36
• @UlrikeFischer: Thanks, works like a charm. Please copy-paste my MWE above into an answer so I can mark it as accepted. – Rody Oldenhuis Jul 31 '14 at 12:42

biblatex warns you if the bib is empty. You could redefine the command used for the message \blx@warn@bibempty:
 \usepackage{biblatex}