From owner-freebsd-arch@FreeBSD.ORG Sun May 28 17:37:52 2006 Return-Path: X-Original-To: arch@freebsd.org Delivered-To: freebsd-arch@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 0DCB316A555 for ; Sun, 28 May 2006 17:37:52 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (vc4-2-0-87.dsl.netrack.net [199.45.160.85]) by mx1.FreeBSD.org (Postfix) with ESMTP id A487443D48 for ; Sun, 28 May 2006 17:37:51 +0000 (GMT) (envelope-from imp@bsdimp.com) Received: from localhost (localhost.village.org [IPv6:::1] (may be forged)) by harmony.bsdimp.com (8.13.4/8.13.4) with ESMTP id k4SHbKc8094030; Sun, 28 May 2006 11:37:20 -0600 (MDT) (envelope-from imp@bsdimp.com) Date: Sun, 28 May 2006 11:37:24 -0600 (MDT) Message-Id: <20060528.113724.1655407378.imp@bsdimp.com> To: phk@phk.freebsd.dk From: "M. Warner Losh" In-Reply-To: <1471.1148836757@critter.freebsd.dk> References: <4479D804.1060106@elischer.org> <1471.1148836757@critter.freebsd.dk> X-Mailer: Mew version 4.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: arch@freebsd.org, julian@elischer.org Subject: Re: A sort of plan for consoles in FreeBSD X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 28 May 2006 17:37:52 -0000 In message: <1471.1148836757@critter.freebsd.dk> "Poul-Henning Kamp" writes: : In message <4479D804.1060106@elischer.org>, Julian Elischer writes: : >M. Warner Losh wrote: : > : >>In message: <4479C171.4050403@elischer.org> : >> Julian Elischer writes: : >>: killing XConsole is not a small matter. people have that when they are : >>: specifically looking for that information : >> : >>Recall that this is only for programs that open /dev/console directly : >>and write to it, like syslogd. : > : >the description makes it sound like xconsole would not be able to show : >kernel error messages. : : xconsole is a hack anyway. : : the correct way would be to have way to connect to syslogd and subscribe : to messages. There's no way to 'connect to syslogd and subscribe to messages' in the current syslogd. In today's world order, the best that it can do is to open a pty, and then hack syslogd.conf to send messages to that pty and then log the results. This takes quiet a bit of code, and there's a number of tricky edge cases to make it work. At least there were back when I created a combination xconsole + syslog display program. And I still didn't have the ability to filter on message time except in real time (since syslogd doesn't print message type). I also had to have two PTYs open (one for syslog messages and one for console messages). If you are going to go down this route, lots of work needs to happen to both xconsole and syslogd (and all other xconsole-like programs). Not saying that it can't be done, but there's a big hunk of work there before people would be happy. Why we can't do as I suggested earlier and just make /dev/console a pseudo-pipe that is fed from #2 and #4 and that has a well documented 'other end interface' for things like xconsole. that would simulate the historical usage of /dev/console well. Warner