From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Jackson <Ian.Jackson@eu.citrix.com>
Subject: Re: Domain Save Image Format proposal (draft B)
Date: Tue, 11 Feb 2014 17:28:43 +0000
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To: David Vrabel <david.vrabel@citrix.com>
Cc: Shriram Rajagopalan <rshriram@cs.ubc.ca>, Stefano Stabellini <stefano.stabellini@eu.citrix.com>, Ian Campbell <ian.campbell@citrix.com>, "Xen-devel@lists.xen.org" <Xen-devel@lists.xen.org>
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David Vrabel writes ("Re: Domain Save Image Format proposal (draft B)"):
> On 11/02/14 16:49, Ian Jackson wrote:
> > I greatly prefer doing forward-compatibility with new record type
> > enums etc. than with version numbers.  Version numbers presuppose a
> > strict global order on all the implementations' capabilities, which is
> > of course not necessarily true in free software.
> 
> I think I quite like this idea.  There would still need to be a central
> repository of record types.

Right.

One thing you can do is like PNG and have separate ranges of record
type numbers for (a) ok to ignore this if not understood and (b) fatal
if not understood.

I think PNG also has subset of the namespace for "private use".

Ian.