What is CMUTrace file?

Hi everyone,

  

I'm a beginner of  NS2. Recently I have being reading NS2 Tutorial, and some
questions came out when reading the Section IX.

At the end of the section, some phase as following:

  

_ Next add informative headers for the CMUTrace file, just before the line
"ns_ run" :_

_puts $tracefd "M 0.0 nn $val(nn) x $val(x) y $val(y) rp $val(adhocRouting)" _

_puts $tracefd "M 0.0 sc $val(sc) cp $val(cp) seed $val(seed)" _

_puts $tracefd "M 0.0 prop $val(prop) ant $val(ant)"_  

  

What is CMUTrace? It's a normal trace file like namtrace? And what are those
means of the codes?

  

Forgive my poor English, it's not my first language.

  

Regards,

Yao