=== modified file 'src/window.c'
--- src/window.c	2008-04-03 02:15:43 +0000
+++ src/window.c	2008-04-29 09:40:34 +0000
@@ -275,6 +278,7 @@
   p->frame = Qnil;
   p->display_table = Qnil;
   p->dedicated = Qnil;
+  p->window_parameters = Qnil;
   p->pseudo_window_p = 0;
   bzero (&p->cursor, sizeof (p->cursor));
   bzero (&p->last_cursor, sizeof (p->last_cursor));
@@ -1325,6 +1329,38 @@
   return w->dedicated;
 }
 
+DEFUN ("window-parameters", Fwindow_parameters, Swindow_parameters,
+       1, 1, 0,
+       doc: /* Return WINDOW's window-parameters.
+               returns nil or an alist where values affect window operations.  */)
+     (window)
+     Lisp_Object window;
+{
+  return decode_window (window)->window_parameters;
+}
+
+
+DEFUN ("set-window-parameter", Fset_window_parameter,
+       Sset_window_parameter, 3, 3, 0,
+       doc: /* set window parameters */)
+     (window, prop, val)
+     Lisp_Object window, prop, val;
+{
+  register struct window *w = decode_window (window);
+  register Lisp_Object old_alist_elt;
+  
+  old_alist_elt = Fassq (prop, w->window_parameters);
+  if (EQ (old_alist_elt, Qnil))
+    w->window_parameters = Fcons (Fcons (prop, val), w->window_parameters);
+  else
+    Fsetcdr (old_alist_elt, val);
+
+  //Fplist_put(w->window_parameters,key,value);
+
+  return w->window_parameters;
+}
+
+
 DEFUN ("window-display-table", Fwindow_display_table, Swindow_display_table,
        0, 1, 0,
        doc: /* Return the display-table that WINDOW is using.
@@ -7714,6 +7771,9 @@
   defsubr (&Sset_window_vscroll);
   defsubr (&Scompare_window_configurations);
   defsubr (&Swindow_list);
+  defsubr (&Swindow_parameters);
+  defsubr (&Sset_window_parameter);           
+           
 }
 
 void

=== modified file 'src/window.h'
--- src/window.h	2008-01-29 02:05:10 +0000
+++ src/window.h	2008-04-29 10:04:07 +0000
@@ -229,6 +229,11 @@
        enlarged. */
     Lisp_Object orig_total_lines, orig_top_line;
 
+    /* an alist with flags that modifies behaviour of certain window operations.
+       currently "pin" and "group" are special
+     */
+    Lisp_Object window_parameters;
+    
     /* No Lisp data may follow below this point without changing
        mark_object in alloc.c.  The member current_matrix must be the
        first non-Lisp member.  */