Update runtime files.
diff --git a/runtime/doc/usr_43.txt b/runtime/doc/usr_43.txt
index 6eaa9c1..8f0820f 100644
--- a/runtime/doc/usr_43.txt
+++ b/runtime/doc/usr_43.txt
@@ -1,4 +1,4 @@
-*usr_43.txt*	For Vim version 7.4.  Last change: 2008 Dec 28
+*usr_43.txt*	For Vim version 7.4.  Last change: 2015 Oct 23
 
 		     VIM USER MANUAL - by Bram Moolenaar
 
@@ -46,6 +46,7 @@
 
 	setlocal softtabstop=4
 	noremap <buffer> <LocalLeader>c o/**************<CR><CR>/<Esc>
+	let b:undo_ftplugin = "setl softtabstop< | unmap <buffer> <LocalLeader>c"
 
 Try editing a C file.  You should notice that the 'softtabstop' option is set
 to 4.  But when you edit another file it's reset to the default zero.  That is
@@ -60,6 +61,11 @@
 |<LocalLeader>| in the mapping is replaced with the value of the
 "maplocalleader" variable.
 
+The line to set b:undo_ftplugin is for when the filetype is set to another
+value.  In that case you will want to undo your preferences.  The
+b:undo_ftplugin variable is executed as a command. Watch out for characters
+with a special meaning inside a string, such as a backslash.
+
 You can find examples for filetype plugins in this directory: >
 
 	$VIMRUNTIME/ftplugin/