Deprecate CI_Config::system_url()
diff --git a/user_guide_src/source/libraries/config.rst b/user_guide_src/source/libraries/config.rst
index b318157..3116b76 100644
--- a/user_guide_src/source/libraries/config.rst
+++ b/user_guide_src/source/libraries/config.rst
@@ -245,4 +245,8 @@
:returns: URL pointing at your CI system/ directory
:rtype: string
- This method retrieves the URL to your CodeIgniter system/ directory.
\ No newline at end of file
+ This method retrieves the URL to your CodeIgniter system/ directory.
+
+ .. note:: This method is DEPRECATED because it encourages usage of
+ insecure coding practices. Your *system/* directory shouldn't
+ be publicly accessible.
\ No newline at end of file