[rabbitmq-discuss] Parsability of rabbitctrl output

[Garrett Smith]

There are some values output by rabbitctrl that are blank/empty, but
these are simply omitted from the output. This makes parsing the
output difficult. E.g.

  rabbitmqctl list_queues name owner_pid memory

In cases where owner_pid is blank, the output line has two tokens,
three otherwise.

Any thoughts on providing a symbol, e.g. "undefined", "-" etc. to help
parsers know when a value is empty?

Garrett