diff --git a/unix/x0vncserver/XPixelBuffer.h b/unix/x0vncserver/XPixelBuffer.h
index 44377df..29b82f5 100644
--- a/unix/x0vncserver/XPixelBuffer.h
+++ b/unix/x0vncserver/XPixelBuffer.h
@@ -43,6 +43,9 @@
 
   virtual int getStride() const { return stride; }
 
+  // Override PixelBuffer's function.
+  virtual void grabRegion(const rfb::Region& region);
+
 protected:
   int stride;
 };