How to redirect already answered incoming call using pjsip?

Question

I use pjsip.dll for creating softphone app. Answering and dialing works fine. Now, I need to redirect already answered incoming call to another sip-user (for example, from number 101 to 104). How to do that? I cannot find function in pjsip sdk docs. I have a C# app (softphone with sipek sdk wrapper), PBX, Asterisk.

Answer 1

Library should have SIP transfer option.

If it have no, freepbx have transfer code like *2(pause 0.1sec), 100(pause 0.1),#, Hangup. Just use DTMF and send that sequence.