(mode-name): Doc fix.

src/ChangeLog

+2008-02-10  Glenn Morris  <rgm@gnu.org>
+
+	* buffer.c (mode-name): Doc fix.
+
 2008-02-09  Dan Nicolaescu  <dann@ics.uci.edu>
 
 	* src/Makefile.in:

src/buffer.c

@@ -5607,7 +5607,8 @@ its hooks should not expect certain variables such as
   DEFVAR_PER_BUFFER ("mode-name", &current_buffer->mode_name,
                      Qnil,
 		     doc: /* Pretty name of current buffer's major mode.
-Usually a string.  See `mode-line-format' for other possible forms.  */);
+Usually a string.  See `mode-line-format' for other possible forms.
+Use the function `format-mode-line' to get the value as a string.  */);
 
   DEFVAR_PER_BUFFER ("local-abbrev-table", &current_buffer->abbrev_table, Qnil,
 		     doc: /* Local (mode-specific) abbrev table of current buffer.  */);