星号拨号计划：如何检测何时成功接听电话？

Question

I'm having a really hard time figuring out if there is a trigger or a way to continue from the Dial action that allows you to detect if the call is answered. It seems like Dial doesn't respond until hangup, busy, or congested . What action or event am I missing that would tell me when the other end of the line actually answers the call? Hoping there is something like this available that I'm just missing:

exten => s,7,Dial(${ARG1},20,rt)       ; Ring the interface, 20 seconds maximum
exten => s,8,Goto(s-${DIALSTATUS},1)                    
; Jump based on status (NOANSWER,BUSY,CHANUNAVAIL,CONGESTION,ANSWER)
exten => s-ANSWER(do something)

Answer 1

Finally figured it out. It involves calling the M flag in the Dial action call. By calling the M flag, you can call a custom macro that will execute immediately after the call is connected/answered.

Ex: Dial(SIP/200,60,M(myCustomMacro))

Hope this helps for any that were also curious.

Answer 2

You can also do a Gosub when call is answered:

asterisk*cli> core show application Dial
...
    U(x[^arg[^...]]):
        x - Name of the subroutine to execute via Gosub
        arg - Arguments for the Gosub routine
Execute via Gosub the routine <x> for the *called* channel before connecting to
the calling channel. Arguments can be specified to the Gosub using '^' as a
delimiter. The Gosub routine can set the variable ${GOSUB_RESULT} to specify
the following actions after the Gosub returns