[ns] how to use trace-queue on wireless node

["Kevin Thankakan" <vin@s-t.au.ac.th>]

Hi,

I need help on trace-queue and queue monitor on wireless node. I have tried the
following code

set n0 [$ns_ node]
set n1 [$ns_ node]

set tracefd [open simple.tr w]
$ns_ trace-queue $n0 $n1 $tracefd

but it didn't work, anyone can give me the example of how to use
trace-queue or queue-monitor. I have read in a NS manual already but I

couldn't find any.

Thanks,
Kevin.