From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=35048 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OCvRj-0005AI-T7 for qemu-devel@nongnu.org; Fri, 14 May 2010 10:01:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OCvRi-0007aO-0R for qemu-devel@nongnu.org; Fri, 14 May 2010 10:00:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:11570) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OCvRh-0007aA-Os for qemu-devel@nongnu.org; Fri, 14 May 2010 10:00:57 -0400 Message-ID: <4BED5718.3060505@redhat.com> Date: Fri, 14 May 2010 09:58:48 -0400 From: Chris Lalancette MIME-Version: 1.0 Subject: Re: [Qemu-devel] Re: [PATCH 1/1] Add -version-simple argument, printing only version number. References: <1273739572-30840-1-git-send-email-Jes.Sorensen@redhat.com> <1273739572-30840-2-git-send-email-Jes.Sorensen@redhat.com> <4BED4E73.2080802@linux.vnet.ibm.com> In-Reply-To: <4BED4E73.2080802@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: Jes.Sorensen@redhat.com, qemu-devel@nongnu.org, crobinso@redhat.com On 05/14/2010 09:21 AM, Anthony Liguori wrote: > On 05/13/2010 03:32 AM, Jes.Sorensen@redhat.com wrote: >> From: Jes Sorensen >> >> Add -version-simple argument for QEMU, printing just the version >> number, without any supporting text. >> > > I'm not a huge fan of the name. > > But what information are we trying to convey? Just major/minor number > or would qemu-kvm also throw some info in there? > > Do version numbers even matter because 0.13 from qemu.git is going to be > a hell of a lot different from 0.13 in RHEL6.x. > > What are the consumers of this information actually doing with it? At the moment libvirt uses it mostly to determine what features are present in a particular version of Qemu that is on the machine. So for instrance, for 0.13 we turn on the JSON flag so we know to use the QMP monitor instead of the text monitor. There are many other examples as well. Now, I agree that this isn't the best way to do it; much better would be a way for libvirt to query the capabilities of Qemu directly and not rely on versions (not the least because of the problem you point out above). But up until now we haven't had a better way to do it. -- Chris Lalancette