[asterisk-users] How to Create Custom Context

[Nitesh Divecha]

Hello All,

Is there any way to write a custom context, where first it checks 
internally to see if the SIP User exist with same DID number, if it does 
route the call internally like calling from one extension to another 
extension, else pass the call to A2Billing to do the billing and use the 
default outbound trunks to terminate the call.

Reason for this is because I have generated my SIP User with real US DID 
and I would like to keep the cost minimum by not sending the local calls 
out on Trunk and receive it back...

For example,

[custom-a2billing]
exten => _XXXXXXXXXX,1,Answer
exten => _XXXXXXXXXX,2,Wait,2
exten => _XXXXXXXXXX,3,_ _ _ _ _ _ _ ; What to fill here to check for 
local calls and it not found send to A2Billing.php
exten => _XXXXXXXXXX,4,DeadAGI(a2billing.php|1)
exten => _XXXXXXXXXX,5,Wait,2
exten => _XXXXXXXXXX,6,Hangup

Any suggestions...?

Cheers,
Nitesh