Alert-Info header in 183 response

Hi All,
I want add Alert-info header in 183 sip response. I added this header by modifying asterisk chan_sip.c file. But I need to add it from “extensions.conf”, how distinctive alerting has been done. I tried with SIPAddHeader() function in “extensions.conf”, I could not success. Please help me in this regard. Because I need to give file path in Alert-Info for playing Announcements.

Girish kumar S

Have you considered installing FreePBX as a front-end? It handles alert headers for you in an elegant fashion without all the manual fiddling with channel programs or .conf files.

I can’t imagine manually configuring an Asterisk system anymore.