Advice on debugging tcl scripts

["T.Hval" <th1@ukc.ac.uk>]

Hello!
Just wondering if anybody has any usefull advice for debugging the tcl
scripts. I am a bit stuck with a test script Im writing to get to know the
multicast functionality, the problem is that no traffic is generated even
though I have set events to happend. I  let a node join a multicast
group, which has a sender that sends CBR traffic, but no traffic appears
when I look at the result in nam.
I am using mcast.tcl in the "ns-2.1b5/tcl/ex" directory as a pattern
(that script do work).

Any hints for a beginner?

Thanks
 
Tor Hval