--- a/mpd2src/fiforeader.h
+++ b/mpd2src/fiforeader.h
@@ -33,7 +33,7 @@
     ~FifoReader();
     bool open();
     bool isblocking() {return m_blocking;}
-    const unsigned char *data(size_t size);
+    const unsigned char *data(size_t size, ssize_t &nread);
 
 private:
     std::string m_fn;