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Extending NS: Adding a Variable to an Object

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• Adding RawPut and GoodPut to TCPSink Object

  

  • Locate the proper class source files: ns/tcp/tcp-sink.h and ns/tcp/tcp-sink.cc

  • Add the variables in the class definition (ns/tcp/tcp-sink.h) file

  • Add "bind()" calls in the class constructor TcpSink::TcpSink() to make associations with TCL variable names

  • Add usage instructions. Here, we update RawPut and GoodPut when data is received (see TcpSink::recv()).

  • Technically, we can use the variable in NS script now, as:
    [$TcpSinkObjectVariable set RawPut]

    [$TcpSinkObjectVariable set GoodPut]

  • However, TCL variable must be initialized in ns/tcl/lib/ns-default.tcl:
    Agent/TCPSink set RawPut 0

    Agent/TCPSink set GoodPut 0