diff --git a/doc/main b/doc/main
new file mode 100644
index 00000000..9fa9c369
--- /dev/null
+++ b/doc/main
@@ -0,0 +1 @@
+after uiQuit or if uiShouldQuit returns nonzero, uiQueueMain's effect is undefined
diff --git a/unix/main.c b/unix/main.c
index 07010cd5..50f308bd 100644
--- a/unix/main.c
+++ b/unix/main.c
@@ -62,7 +62,6 @@ static gboolean doqueued(gpointer data)
 	return FALSE;
 }
 
-// TODO document that the effect of calling this function after uiQuit() is called (either directly or via a nonzero return to uiShouldQuit()) is undefined
 void uiQueueMain(void (*f)(void *data), void *data)
 {
 	struct queued *q;