Add extra generated RPM requires - how?

[Richard W.M. Jones]

For libguestfs [RHBZ#547496] I want to add some extra 'Requires'
dependencies by running a shell script over a particular file that
gets generated during the build.

What's the best way, or a way, to do this?

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-p2v converts physical machines to virtual machines.  Boot with a
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