From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:60775)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <pbonzini@redhat.com>) id 1V4VI0-0001vI-2Z
	for qemu-devel@nongnu.org; Wed, 31 Jul 2013 08:14:06 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <pbonzini@redhat.com>) id 1V4VHu-0002Cr-2z
	for qemu-devel@nongnu.org; Wed, 31 Jul 2013 08:13:59 -0400
Received: from mx3-phx2.redhat.com ([209.132.183.24]:46669)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <pbonzini@redhat.com>) id 1V4VHt-0002CW-Ro
	for qemu-devel@nongnu.org; Wed, 31 Jul 2013 08:13:54 -0400
Date: Wed, 31 Jul 2013 08:13:48 -0400 (EDT)
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <1630661476.7468316.1375272828246.JavaMail.root@redhat.com>
In-Reply-To: <20130731085715.GD3090@dhcp-200-207.str.redhat.com>
References: <1374762197-7261-1-git-send-email-pbonzini@redhat.com>
	<1374762197-7261-14-git-send-email-pbonzini@redhat.com>
	<20130730151353.GF2475@dhcp-200-207.str.redhat.com>
	<51F7DA48.1060807@redhat.com>
	<20130731085715.GD3090@dhcp-200-207.str.redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH v3 13/19] qemu-img: add a "map" subcommand
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Kevin Wolf <kwolf@redhat.com>
Cc: pl@kamp.de, qemu-devel@nongnu.org, stefanha@redhat.com

> The documentation patch contains a line like this:
> 
> 0       131072       2        327680
> 
> A heading line and tabs (or even better, fixed printf column widths)
> sounds good, but I think if it's really only for human users and not for
> shell scripts, we can further improve the output:
> 
> Offset      Length      Mapped to       File
> 
> 0         + 128k     -> 320k            /tmp/backing.qcow2
> 128k      + 256k     -> 2M              /tmp/overlay.qcow2

Changing depth to file is a good idea, but it rules out any
possibility of using it in shell scripts due to newlines in
files.  I don't think + and -> add much and I'd rather leave
them out.

I'm quite ambivalent with respect to hexadecimal vs. decimal,
of course hex is more readable.  Some tools may prefer decimal,
but then x=`eval echo "\$(($x))"` is an easy way to convert.

Any user of this stuff is going to be quite technical, so in
the end I would go for this:

Offset  Length      Mapped to       File
0x0     0x20000     0x50000         /tmp/backup.qcow2

Paolo