From owner-freebsd-hackers@FreeBSD.ORG Sun Sep 12 13:08:01 2010 Return-Path: <owner-freebsd-hackers@FreeBSD.ORG> Delivered-To: freebsd-hackers@freebsd.org Received: by hub.freebsd.org (Postfix, from userid 1233) id C4F711065675; Sun, 12 Sep 2010 13:08:01 +0000 (UTC) Date: Sun, 12 Sep 2010 13:08:01 +0000 From: Alexander Best <arundel@freebsd.org> To: Jilles Tjoelker <jilles@stack.nl> Message-ID: <20100912130801.GA23538@freebsd.org> References: <4C8A81D9.5020905@rawbw.com> <20100910194600.GB60815@stack.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100910194600.GB60815@stack.nl> Cc: Yuri <yuri@rawbw.com>, freebsd-hackers@freebsd.org Subject: Re: Why I can't trace linux process's childs with truss? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD <freebsd-hackers.freebsd.org> List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, <mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe> List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers> List-Post: <mailto:freebsd-hackers@freebsd.org> List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help> List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, <mailto:freebsd-hackers-request@freebsd.org?subject=subscribe> X-List-Received-Date: Sun, 12 Sep 2010 13:08:01 -0000 On Fri Sep 10 10, Jilles Tjoelker wrote: > On Fri, Sep 10, 2010 at 12:07:05PM -0700, Yuri wrote: > > I am trying to get the log of all system calls that skype makes with > > truss -f /usr/local/share/skype/skype > > For some reason the resulting log only has the leading process calls and > > nothing from it's 8 childs. > > Truss doesn't show any 'cloned' processes. Is this a bug in truss that > > it doesn't follow 'cloned' processes? > > > Is there any workaround or other way I can debug skype? strace doesn't > > work on amd64. > > I am primarily interested why it can't read /dev/video0 device, created > > by webcamd. > > Try using ktrace instead of truss. You will need devel/linux_kdump from > ports to decode the resulting ktrace.out. there's a PR related to this "issue" [1]. so is truss missing this functionality or is this in fact a feature, because truss musn't be used on any non freebsd executable? if that is the case i vote to add a CAVEATS section to the truss(1) manual so people rather use ktrace in combination with linux_kdump. cheers. alex [1] http://www.freebsd.org/cgi/query-pr.cgi?pr=150262 > > Alternatively, if you're familiar with dtrace, you could try that. > > -- > Jilles Tjoelker -- a13x