From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NwbQH-00066h-EM for qemu-devel@nongnu.org; Tue, 30 Mar 2010 09:24:01 -0400 Received: from [140.186.70.92] (port=42837 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NwbQF-00064H-Om for qemu-devel@nongnu.org; Tue, 30 Mar 2010 09:24:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1NwbQD-00076E-J8 for qemu-devel@nongnu.org; Tue, 30 Mar 2010 09:23:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37196) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1NwbQD-000763-8C for qemu-devel@nongnu.org; Tue, 30 Mar 2010 09:23:57 -0400 Message-ID: <4BB1FB48.3070602@redhat.com> Date: Tue, 30 Mar 2010 15:23:20 +0200 From: Kevin Wolf MIME-Version: 1.0 References: <445AFA0A-43C1-4F8A-929E-EE3735E93999@suse.de> <4BB1EEF4.3070407@redhat.com> <5C4F242F-0AC7-4C25-AE6B-C3D12AFCE091@suse.de> <4BB1F350.2000100@redhat.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: qemu-img help missing backing file List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Juan Quintela Cc: Alexander Graf , qemu-devel Developers Am 30.03.2010 15:04, schrieb Juan Quintela: > Kevin Wolf wrote: >> Am 30.03.2010 14:32, schrieb Alexander Graf: >>> >>> On 30.03.2010, at 14:30, Kevin Wolf wrote: >>> >>>> Am 30.03.2010 14:22, schrieb Alexander Graf: >>>>> Howdy, >>>>> >>>>> I just wanted to create a backed qcow2 image and was irritated by qemu-img not showing me the correct command line option. It's just missing from the list: >>>> [...] >>>>> Is this intentional? The actual command still works: >>>>> >>>>>> agraf@s390t27:~/git/qemu> qemu-img-kvm create -f qcow2 -b /media/studio/images/SUSE/s390/sles11.raw /dev/shm/sles11-zipl.qcow2 >>>>>> Formatting '/dev/shm/sles11-zipl.qcow2', fmt=qcow2 size=21474836480 backing_file='/media/studio/images/SUSE/s390/sles11.raw' encryption=off cluster_size=0 >>>> >>>> -b still works to maintain compatibility with older versions. The >>>> documented way is -o backing_file=foo (the qemu-img output you quote >>>> even contains this option). >>> >>> Interesting O_o. Maybe it'd be a good idea to give some examples in the help output? The same way the -e and -b options were having examples there too. That really makes them easier to find. >> >> Feel free to submit a patch. ;-) >> >> Examples sound like an easy way to make these features more visible >> again. Even better, but a bit more work, would be to include a >> dynamically generated list of all supported options like this: >> >> backing_file: File name of a base image (qcow, qcow2, vmdk) >> backing_fmt: Image format of the base image (qcow2) >> encryption: Encrypt the image (qcow, qcow2) > > You can look at how this was done for -cpu > > you do -cpu ?model > > and it list the models. We do have something like this for block options, -o ? displays this information - however, it displays them only for a given format, just like cpu -? displays them only for one architecture. What is different with my suggestion is that you would iterate over all image formats and coalesce duplicates into a single line. It shouldn't be really hard, but a little more work than just changing the help string to contain some examples. Kevin