Analyse the B party and terminate the call

Hi all, :?:

I’m running asterisk 1.6 with freepbx. The system is up and running finely. But i need to do something special with asterisk. i have a txt file wish is contain list of b party number. This txt file is updating time to time. May be every few seconds.
My requirement is i need to match this txt file number list with the call B party number. If both get match i need to release the call.

My real requirement is, i need to deny duplicate phone calls to b party number. That mean if one call come to specific B party number and after it get released and if again someone call to that specific B party second call should deny. Above mentioned txt file contain all b party number which are going thru the server. I already created that part.

But don’t know how to match the called B part number wit that txt file and deny if the number get match.

Please advice.

Thx lot.