Control FreeSWITCH, intercept a session with Perl scripts.These examples rely on mod_perl scripting, initially published by Mitch Capper.
Console IVR Example
Live Session Intercept IVR Example
This is a simple script to show how you can get the list of current sessions, present them to the user, and let them choose one to take over. This is part of one of my larger dial plans but it should be fairly obvious about how to integrate it into your own. Originally we used this with cepstral which allows you to announce caller ID names and such too, but this is a simpler version which doesn't require it. Each call is actually made up of two sessions, so we use some logic to try and skip the session we don't care about. This does assume 4 digit extensions always calling a non sip address or non sip address calling a 4 digit extension. Integrate this with Console IVR Example to provide an easy way to dial in on a cell phone and take over an active session for example.