On 02/12/2010 01:38 PM, Brian Harring wrote:
> On Fri, Feb 12, 2010 at 12:54:21PM -0800, Zac Medico wrote:
>> Hi,
>>
>> I'm thinking about adding a UUID file in /var/db/pkg, for comparing
>> installed packages to binary packages. We already have BINPKGMD5,
>> but the problem with that is that the MD5 of a binary package
>> changes when it's updated for package moves. A UUID would be
>> assigned at build time and remain constant thereafter. We can use
>> python's uuid.uuid4() function to generate a random UUID. Any
>> suggestions for alternative approaches?
> 
> Purpose?
> ~harring

If you build binary packages for installation on multiple systems,
and periodically have to rebuild packages for various reasons
(revdep-rebuild or whatnot), it makes it easier to know whether a
particular system has the latest build installed. Then you can
create a package set that reinstalls any installed packages that are
not the latest build.

It's basically a catch-all for rebuilds that aren't tracked by other
kinds of metadata yet. Eventually, we should introduce metadata to
indicate when things need to be reinstalled, as discussed in this bug:

  https://bugs.gentoo.org/show_bug.cgi?id=192319

In the mean time, it's nice to have a catch-all for keeping systems
synchronized with the latest builds. We may want to consider
including it in the $PKGDIR/Packages file as a convenience for
binhost users.
-- 
Thanks,
Zac