diff --git a/src/ex_getln.c b/src/ex_getln.c
index 258548e..2616afc 100644
--- a/src/ex_getln.c
+++ b/src/ex_getln.c
@@ -4485,6 +4485,15 @@
 
     return cmdwin_result;
 }
+
+/*
+ * Return TRUE if in the cmdwin, not editing the command line.
+ */
+    int
+is_in_cmdwin(void)
+{
+    return cmdwin_type != 0 && get_cmdline_type() == NUL;
+}
 #endif // FEAT_CMDWIN
 
 /*