Index: display.texi
===================================================================
RCS file: /sources/emacs/emacs/doc/lispref/display.texi,v
retrieving revision 1.52
diff -u -r1.52 display.texi
--- display.texi	1 Sep 2009 02:54:16 -0000	1.52
+++ display.texi	24 Sep 2009 13:51:22 -0000
@@ -1269,6 +1269,12 @@
 current buffer.
 @end defun
 
+@defun copy-overlay overlay
+This function will return a copy of @var{overlay}, with the exception
+of the insertion marker types, which will always be set to their
+default values.
+@end defun
+
   Here are some examples:
 
 @example