From owner-freebsd-hackers@FreeBSD.ORG Tue Jun 22 01:29:54 2004 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 0A07F16A4CE; Tue, 22 Jun 2004 01:29:54 +0000 (GMT) Received: from sccrmhc11.comcast.net (sccrmhc11.comcast.net [204.127.202.55]) by mx1.FreeBSD.org (Postfix) with ESMTP id 98D2643D46; Tue, 22 Jun 2004 01:29:51 +0000 (GMT) (envelope-from julian@elischer.org) Received: from interjet.elischer.org ([24.7.73.28]) by comcast.net (sccrmhc11) with ESMTP id <2004062201294201100r57dfe>; Tue, 22 Jun 2004 01:29:48 +0000 Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id SAA43577; Mon, 21 Jun 2004 18:29:39 -0700 (PDT) Date: Mon, 21 Jun 2004 18:29:38 -0700 (PDT) From: Julian Elischer To: "Daniel O'Connor" In-Reply-To: <200406221031.51655.doconnor@gsoft.com.au> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: freebsd-hackers@freebsd.org cc: hackers@freebsd.org cc: Eugene Grosbein Subject: Re: writing ktrace output to serial port X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Jun 2004 01:29:54 -0000 On Tue, 22 Jun 2004, Daniel O'Connor wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On Sun, 20 Jun 2004 23:29, Eugene Grosbein wrote: > > So I want to see what is happening just before my mplayer crashes the > > kernel. The problem is that ktracing mplayer does not help as filesystem > > can't keep ktrace.out being written just before crash. I tried 'sync' > > mount, > > it does not help too. > > > > I decided to divert ktrace.out to /dev/cuaa0 so another FreeBSD will keep > > it. However, ktrace() in src/sys/kern/kern_trace.c does not permit writing > > to non-regular file. Why? > > The actual syscall passes a filename, not a file descriptor so you'd have to > change that (or make a new syscall) if you wanted to change it at all :( > > It would be nice to be able to ktrace() to an fd (eg socket or pipe) though :) > > See ktrace() in /usr/src/sys/kern/kern_ktrace.c:494 > > As for your problem.. > Can you NFS mount? If you have no ethernet you could NFS mount over > PPP/SLIP :) > (or PLIP if you have a parallel port) > it would be relatively easy to sent it to a netgraph ng_ksocket node and have the record sent out as a udp packet :-)