bgpctl(8) community question

[OpenBSD 6.5-STABLE, up to date]

When using bgpctl(8), I'm able to do almost everything I need, but I'm
having trouble figuring out how to do one thing:

How do I show routes that do NOT have a community (or ext-community, or
large-community) attribute?

The best I can come up with so far is a fairly ugly AWK script that
buffers the detailed route output, then emits it if it doesn't see a
Communities: line. Am I missing a better way?

Thanks,
-Adam

N.B. manually looking through N sets of DFZ route tables isn't going to
happen, I need a mostly-automatic solution.