[asterisk-users] Dial() - any way to limit waiting for a "RINGING" state?

[Anton]

Hello!

Just trying to find out how to limit waiting for a "RINGING" 
state for an initiated call by Dial() - This is necessary 
since I want to inform the CALLER that destination is not 
available if RINGING state was not received within, say 20 
seconds. This applies for mostly SIP and IAX2 calls - 

Is that possible without hacking the app_dial?

Regards,
Anton.