diff --git a/unix/vncviewer/parameters.h b/unix/vncviewer/parameters.h
index 6505aa8..7e4960a 100644
--- a/unix/vncviewer/parameters.h
+++ b/unix/vncviewer/parameters.h
@@ -35,6 +35,7 @@
 extern rfb::BoolParameter acceptClipboard;
 extern rfb::BoolParameter sendClipboard;
 extern rfb::BoolParameter sendPrimary;
+extern rfb::StringParameter desktopSize;
 extern rfb::BoolParameter fullScreen;
 extern rfb::StringParameter geometry;
 extern rfb::BoolParameter customCompressLevel;