Incorrect example code in the tutorial

[Peter Braun]

Hello!

I'm going through the NS-3 tutorial. Actually I believe that the example code provided in the 'Tracing / Connect with Config' section is incorrect.

This code is provided as an example:

Ptr<Object> theObject = wifiStaNodes.Get (nWifi - 1);
theObject->TraceConnect ("CourseChange", MakeCallback (&CourseChange));

Actually what it does is to try to connect Node's CourseChange Attribute to CourseChange() callback. Although Node does not have such attribute.

Instead I think the correct code would be something like this:

Ptr<Object> o = wifiStaNodes.Get (nWifi - 1)->GetObject<MobilityModel>();
o->TraceConnect("CourseChange", "ctx", MakeCallback (CourseChange));

Please cross check.

Thanks,

Peter

[Tommaso Pecorella]

Hi Peter,

sorry if I didn't reply earlier. You're totally right, the tutorial code won't work.

It won't work because:

1) TraceConnect wants 3 arguments, and in the examples there are 2, and

2) The connection won't work, because TraceConnect doesn't search into aggregated objects. As a consequence, it won't find any trace named "CourseChange" in the Node object.

We'll fix the tutorial, thanks.

Cheers,

T.