* lisp/frame.el (frame-background-mode): Doc fix.

Fixes: debbugs:15226

2 files changed, 8 insertions, 2 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 2e639615c25..2dda52f82ed 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2013-09-01  Glenn Morris  <rgm@gnu.org>
+
+        * frame.el (frame-background-mode): Doc fix.  (Bug#15226)
+
 2013-08-30  Glenn Morris  <rgm@gnu.org>
 
         * emacs-lisp/bytecomp.el (byte-recompile-directory):
diff --git a/lisp/frame.el b/lisp/frame.el
index 79394bd305b..66f6b910940 100644
--- a/lisp/frame.el
+++ b/lisp/frame.el
@@ -872,8 +872,10 @@ If there is no frame by that name, signal an error."
   "The brightness of the background.
 Set this to the symbol `dark' if your background color is dark,
 `light' if your background is light, or nil (automatic by default)
-if you want Emacs to examine the brightness for you.  Don't set this
-variable with `setq'; this won't have the expected effect."
+if you want Emacs to examine the brightness for you.
+
+If you change this without using customize after Emacs has started,
+you should use `frame-set-background-mode' to update existing frames."
   :group 'faces
   :set #'(lambda (var value)
            (set-default var value)