Blocks with message input and output only

Hi Guys,

How to write blocks that have only message input and outputs only? I
have derived from gr:block, and in most cases it seems to work, but if
I put together a test that has no streams, then the whole graph stops
I think prematurely. How to ensure that a flow graph works with
messages only?

Miklos

Sorry, everything works as expected (needs a little wait at the
beginning). Miklos