1 files changed, 1 insertions, 0 deletions
diff --git a/tmux.h b/tmux.h
index 42cac02f..fc04bfe9 100644
--- a/tmux.h
+++ b/tmux.h
@@ -137,6 +137,7 @@ enum {
 
 	/* Mouse keys. */
 	KEYC_MOUSE, /* unclassified mouse event */
+	KEYC_DRAGGING, /* dragging in progress */
 	KEYC_MOUSE_KEY(MOUSEDOWN1),
 	KEYC_MOUSE_KEY(MOUSEDOWN2),
 	KEYC_MOUSE_KEY(MOUSEDOWN3),