[ns] Which is the final file/code that handles a packet at the destination?

[Ahsa]

Hello,
 Could you please tell me which file/code in ns is responsible for 
processing a cbr packet, and discard it (after writing any traces)  as it 
has reached its destination and does not need to be forwarded again? The 
code which calls on the cmu-trace for the "agent" tracing of the 
reception of the packet seems to be the final task before the packet is 
forwarded (sent to the routing agent)  or discarded if it has reached its 
destination, but I could not locate where this code actually is. Could 
anyone please guide me?
 Thanks.
 Ma
 
Send instant messages to your online friends http://au.messenger.yahoo.com