diff --git a/vncviewer/parameters.h b/vncviewer/parameters.h
index 2b4c039..9827b14 100644
--- a/vncviewer/parameters.h
+++ b/vncviewer/parameters.h
@@ -49,6 +49,8 @@
 extern rfb::StringParameter geometry;
 extern rfb::BoolParameter remoteResize;
 
+extern rfb::BoolParameter listenMode;
+
 extern rfb::BoolParameter viewOnly;
 extern rfb::BoolParameter shared;