diff --git a/binder/android/os/IVold.aidl b/binder/android/os/IVold.aidl
index 1736829..d47f113 100644
--- a/binder/android/os/IVold.aidl
+++ b/binder/android/os/IVold.aidl
@@ -23,6 +23,7 @@
 interface IVold {
     void setListener(IVoldListener listener);
 
+    void monitor();
     void reset();
     void shutdown();
     void mountAll();