querying the registry for reverse dependencies

[René J.V. Bertin]

Hi,

A variant of my earlier question: is there a magic formula to query the registry which files (and/or ports) depend on a given binary file? IOW, an elegant alternative to something like

%> sudo bzip2 -v foo
%> sudo port -v rev-upgrade
%> sudo bunzip2 foo.bz2

Thanks,
R.