route changes triggered script

Dear All,

Is there any way to create a script which run when there is a change in the routing table? I would like to make a mechanism that triggered by a bgp routing update. Shortly: when my fortigate get a /32 prefix via bgp (from a certain subnet), then I have to add manually a proxy-arp for that /32.

Any advices or key-words are appreciated!

Thank you very much