--- /dev/null
+/**
+ * Implements hook_file_update().
+ */
+function {{ machine_name }}_file_update($file) {
+ $file_user = user_load($file->uid);
+ // Make sure that the file name starts with the owner's user name.
+ if (strpos($file->filename, $file_user->name) !== 0) {
+ $old_filename = $file->filename;
+ $file->filename = $file_user->name . '_' . $file->filename;
+ $file->save();
+
+ watchdog('file', t('%source has been renamed to %destination', array('%source' => $old_filename, '%destination' => $file->filename)));
+ }
+}