Does openSession need to return the sessionId and session url?

[wjdhamilton]

The practical uses of these two values are achieved by the listen function which is internal to the module...

[wjdhamilton]

OK, the Id is used to create a control connection so that's still required.

[wjdhamilton]

Actually the url is used by control as well...

Perhaps it would be better if the entire (id,url,chan) tuple were passed to control which then returned the channel? This would be more convenient from the perspective of monadic function application...