diff --git a/src/proto/window.pro b/src/proto/window.pro
index 3c511e3..05b6b9d 100644
--- a/src/proto/window.pro
+++ b/src/proto/window.pro
@@ -87,4 +87,5 @@
 int win_gotoid(typval_T *argvars);
 void win_id2tabwin(typval_T *argvars, list_T *list);
 int win_id2win(typval_T *argvars);
+void win_findbuf(typval_T *argvars, list_T *list);
 /* vim: set ft=c : */