(syms_of_buffer): Doc fixes.

src/buffer.c

@@ -3809,7 +3809,7 @@ Each window can have its own, overriding display table.");
     "Don't ask.");
 */
   DEFVAR_LISP ("before-change-function", &Vbefore_change_function,
-	       "Function to call before each text change.\n\
+      "If non-nil, a function to call before each text change (obsolete).\n\
 Two arguments are passed to the function: the positions of\n\
 the beginning and end of the range of old text to be changed.\n\
 \(For an insertion, the beginning and end are at the same place.)\n\
@@ -3820,11 +3820,12 @@ don't call any before-change or after-change functions.\n\
 That's because these variables are temporarily set to nil.\n\
 As a result, a hook function cannot straightforwardly alter the value of\n\
 these variables.  See the Emacs Lisp manual for a way of\n\
-accomplishing an equivalent result by using other variables.");
+accomplishing an equivalent result by using other variables.\n\n\
+This variable is obsolete; use `before-change-functions' instead.");
   Vbefore_change_function = Qnil;
 
   DEFVAR_LISP ("after-change-function", &Vafter_change_function,
-	       "Function to call after each text change.\n\
+      "If non-nil, a Function to call after each text change (obsolete).\n\
 Three arguments are passed to the function: the positions of\n\
 the beginning and end of the range of changed text,\n\
 and the length of the pre-change text replaced by that range.\n\
@@ -3837,7 +3838,8 @@ don't call any before-change or after-change functions.\n\
 That's because these variables are temporarily set to nil.\n\
 As a result, a hook function cannot straightforwardly alter the value of\n\
 these variables.  See the Emacs Lisp manual for a way of\n\
-accomplishing an equivalent result by using other variables.");
+accomplishing an equivalent result by using other variables.\n\n\
+This variable is obsolete; use `after-change-functions' instead.");
   Vafter_change_function = Qnil;
 
   DEFVAR_LISP ("before-change-functions", &Vbefore_change_functions,