# File lib/core/tracker.rb, line 29
    def modifications()
      return nil if (state != MODIFIED)
      d = Cproton.pn_delivery_remote(@impl)
      {
       :failed => Cproton.pn_disposition_is_failed(d),
       :undeliverable => Cproton.pn_disposition_is_undeliverable(d),
       :annotations => Codec::Data.to_object(Cproton.pn_disposition_annotations(d))
      }
    end