About ns

[Liu Xiaoyun <engp9264@nus.edu.sg>]

hi,
I just add some source code to ns and make it.
There are no errors when making but when the ns runs, it exits with error
code 1.
Some tcl codes in ns-lib.tcl are shown. The last is:

Simulator instproc abstract-tcp {} {
$self instvar TahoeAckfsm_ RenoAckfsm_ TahoeDelAckfsm_ RenoDelAckfsm_
dropper_ 
$self set TahoeAckfsm_ [new FSM/TahoeAck]
$self set RenoAckfsm_ [new FSM/RenoAck]
$self set TahoeDelAckfsm_ [new FSM/TahoeDelAck]
$self set RenoDelAckfsm_ [new FSM/RenoDelAck]
$self set nullAgent_ [new DropTargetAgent]
}

How can I resolve this problem? Any suggestions?

Thanks

Xiaoyun