diff --git a/core/includes/file.inc b/core/includes/file.inc
index 025fbde..fea4c96 100644
--- a/core/includes/file.inc
+++ b/core/includes/file.inc
@@ -448,7 +448,8 @@ function file_valid_uri($uri) {
  *
  * @see file_copy()
  *
- * @deprecated
+ * @deprecated in Drupal 8.2.x-dev, will be removed before Drupal 9.0.0.
+ *   Use \Drupal\Core\File\UnmanagedFileHandler::copy().
  */
 function file_unmanaged_copy($source, $destination = NULL, $replace = FILE_EXISTS_RENAME) {
   try {