​While I am executing a Macro on the called channel, right after the call connects​, I need to execute an app on the master channel, from inside that macro, specifically, SendDTMF. If I execute it now, it send a text message to the Callee, when my app needs to send it to the caller.

I could use set(master_channel(variable)=XXX), but then how do I execute some code on the master channel. Note that I could send the name of the master channels to the Macro M(Name^parameter), but then how do I execute SendDtmf on the identified Master Channel?