É think there is not such tool to do what you want

On Mon, Nov 3, 2008 at 2:17 PM, Momesso Andrea <momesso.andrea@gmail.com>wrote:

> Is there a way to to update svn packages only when there are updates in
> the svn source?
>
> Actually I use a script to grep "9999" from eix -I output and put all
> those packages in a package set, then I have a cron job to rebuild this
> set weekly.
>
> What I'd like to do is to only fetch the svn sources, and rebuild the
> packages if sources have been updated since last build, saving lots of
> compilations.
>
> Does portage (or any other tool) provide a way to do it?
>