Re: Change in xm interface

[Ewan Mellor <ewan@xensource.com>]

On Fri, Feb 17, 2006 at 03:06:00PM -0600, Anthony Liguori wrote:

> This is a great patch, I just want to make sure everyone who has written 
> a tool against xm that is perhaps screen scrapping the output of xm 
> block-list or xm network-list that the interface has changed.
> 
> You will now have to use --long to get the same S-Expression output.

Your concern is perfectly reasonable.  On that note though, could I
emphasise

  a) Screen-scraping xm is a bad idea.  There is an interface straight
  into xend that one can use for integration (the same interface that xm
  uses).  This will avoid such hackery, and make it an awful lot easier
  to maintain backwards compatibility.  xm is for humans to use, not
  tools.

  b) There is no guarantee that any interface inside domain 0, be it
  to the tools, or even to Xen, are fixed.  The only interfaces that are fixed
  at the moment are the interfaces used by guests.  Everything else is
  subject to change at any time.  Of course, it's in everyone's
  interests that these interfaces become fixed in the future, but
  there's plenty of work that has to go into them yet before we could
  claim that they are supportable in the long term.

> Perhaps this sort of changes should be announced on xen-announce in the 
> future?  Is there such a list?

That list is xen-devel, for the moment.  I'm not sure there's any value
in having a separate list -- anyone who's developing products that sit
on top of Xen _really_ needs to be reading xen-devel anyway -- the
project simply isn't mature enough for you to get away without doing
that.

Ewan.