[mosquitto-dev] When is the publish callback called?

["Mark Pilant" <lpilant@xxxxxxxxxx>]

I'm looking to do some publish timing tests, client to broker (and back?); now that I have my test program running (thanks Roger).

Looking at the documentation, it isn't entirely clear when the publish callback (or any other callback for that matter) is called; which I would assume depends on the QoS level.

Here is what I would have expected: QoS 0, after the message is sent (not necessarily queued to be sent) and QoS 1 and 2, when the broker confirms the message has been received. However, this is not what I'm seeing. What I'm seeing appears to be after the message is sent (queued?) for QoS 0 and 1. I haven't tested QoS 2.

Is my expectation correct? If not, is there some way (API call, option, etc.) to accomplish this?

Thanks in advance.

- Mark