Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753899AbcK0Vij (ORCPT ); Sun, 27 Nov 2016 16:38:39 -0500 Received: from out5-smtp.messagingengine.com ([66.111.4.29]:60353 "EHLO out5-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752132AbcK0Vic (ORCPT ); Sun, 27 Nov 2016 16:38:32 -0500 X-ME-Sender: X-Sasl-enc: 0KDizw4MF3wD0GisSAieF8yLpjAOIyPdz1wmQDOIcBZz 1480282653 Date: Sun, 27 Nov 2016 21:37:30 +0000 From: Andrey Utkin To: Manuel =?iso-8859-1?Q?Sch=F6lling?= Cc: plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, jslaby@suse.cz, gregkh@linuxfoundation.org, kilobyte@angband.pl, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 0/3] console: Add persistent scrollback buffers for all VGA consoles Message-ID: <20161127213730.GO11418@dell-m4800.home> References: <20161123173340.GA24872@angband.pl> <1480265509-20922-1-git-send-email-manuel.schoelling@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1480265509-20922-1-git-send-email-manuel.schoelling@gmx.de> User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1720 Lines: 40 Hi Manuel, I've just patched next-20161125 with this set and given it a run. Scrollback persistence works fine, just as in earlier versions. This time I didn't forget to test clear operation. The only important concern is that after logout, the scrollback is not wiped by /bin/login or /sbin/agetty (not sure who of them is responsible for that). What do you see on your workstations in this case? I guess we need to do something of the following: - catch some control character sequences to wipe the scrollback - indicate (by some flag) some feature capability for this - request update in terminfo database or whatever, to let ncurses know that it is capable of scrollback wiping by some control charater sequences Some useless notes follow. I see the user experience is subpar to what I'm accustomed to (I use Konsole and "Clear Scrollback and Reset" action, default shortcut is Ctrl+Shift+K). The strange behaviour moments have nothing to do with current patchset but are properties of vgacon, though. (I compared it with another PC which runs without this patchset, and it looks like it runs vgacon, too, however, I'm not sure how to ensure this at runtime.) clear(1) doesn't wipe the scrollback at all, it is still reachable, all of it. echo -e "\e[3J" seems to wipe the scrollback, but if you do it several times in a row, every time you (or at last I do) get your prompt a bit lower, so after many times you end up with blank screen and the prompt at the bottom of the screen. Have you encountered this, or is it something specific to my setup (I use bash prompt spanning to multiple lines, and calling "stty sane" from inside every PS1 evaluation. I can share the config if you request it).