Make scroll-bar-adjust-thumb-portion customizable, adjust documentation.

* lisp/cus-start.el (all): Add scroll-bar-adjust-thumb-portion.

* src/xterm.c (syms_of_xterm): Adjust documentation for
scroll-bar-adjust-thumb-portion.

2 files changed, 11 insertions, 4 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index ce6ce861a79..31f119160ff 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2013-01-11  Jan Djärv  <jan.h.d@swipnet.se>
+
+        * xterm.c (syms_of_xterm): Adjust documentation for
+        scroll-bar-adjust-thumb-portion.
+
 2012-12-31  Adam Sjøgren  <asjo@koldfront.dk>
 
         * xterm.c (scroll-bar-adjust-thumb-portion): New variable to
diff --git a/src/xterm.c b/src/xterm.c
index cbae1bc4b0d..26d40859ed3 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -10789,10 +10789,12 @@ With MS Windows or Nextstep, the value is t.  */);
 
   DEFVAR_BOOL ("scroll-bar-adjust-thumb-portion",
                scroll_bar_adjust_thumb_portion_p,
-               doc: /* Non-nil means adjust the thumb in the
-scroll bar to be less likely to resize which looks better.
-Set to nil if you want the thumb to fill the whole scroll bar
-when the entire buffer is visible.  */);
+               doc: /* Adjust thumb for overscrolling for Gtk+ and MOTIF.
+Non-nil means adjust the thumb in the scroll bar so it can be dragged downwards
+even if the end of the buffer is shown (i.e. overscrolling).
+Set to nil if you want the thumb to be at the bottom when the end of the buffer
+is shown.  Also, the thumb fills the whole scroll bar when the entire buffer
+is visible.  In this case you can not overscroll.  */);
   scroll_bar_adjust_thumb_portion_p = 1;
 
   staticpro (&last_mouse_motion_frame);