Re: comint-preoutput-filter-functions and flickering redisplay in TTY

[Nicolas Richard]

Mario Lang <address@hidden> writes:
> To reproduce: Install chess.el, call M-x chess-ics RET, login to
> freechess.org (as guest is OK), and wait a bit.  Your screen (at least in -nw 
> mode)
> should start to flicker noticeably every once in a while.
>
> Any ideas why?

I tried it in my GUI emacs (just to try chess.el, in fact) and noticed
very frequent recentering of my window, even when not in the *chess-ics*
buffer.

By tracing "recenter" I found that tabulated-list-print calls (recenter)
without checking what the selected window is. 

here's the patch I applied, perhaps you can try it out and see if it
fixes the problem for you.

diff --git a/lisp/emacs-lisp/tabulated-list.el 
b/lisp/emacs-lisp/tabulated-list.el
index d0d71dd..dd1166f 100644
--- a/lisp/emacs-lisp/tabulated-list.el
+++ b/lisp/emacs-lisp/tabulated-list.el
@@ -323,7 +323,9 @@ to the entry with the same ID element as the current line."
     (if saved-pt
        (progn (goto-char saved-pt)
               (move-to-column saved-col)
-              (recenter))
+              (when (eq (window-buffer (selected-window))
+                         (current-buffer))
+                 (recenter)))
       (goto-char (point-min)))))
 
 (defun tabulated-list-print-entry (id cols)

-- 
Nico.