Things just don't work that way Study the tutorials mentioned here: http://inesc-0.tagus.ist.utl.pt/~pmsrve/ns2/ns2_beginners.html#_Toc128325749 > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf > Of Robert Luke > Sent: terça-feira, 14 de Março de 2006 15:24 > To: ns-users > Subject: [ns] Newbie ns-2/OTcl question > > > I am still a newbie at ns-2 and have a question that is driving me > crazy. I have set up a very simple ns-2 simulation in which there are > two nodes connected by a duplex link. I am sending a single FTP > packet from one node to the other. I've attached the ns-2 input code > to the end of this email. > > My question is this: I can get an object handle for the $ftp0 object > by including a statement that says > > puts "ftp0 = $ftp0" > > But how can I "catch" that single ftp packet in OTcl as it is being > sent so that I can find the object handle for that packet and print > out some of its attributes such as size, contents, class, superclass, > etc.? > > This has got to be such a simple question but I can't for the life of > me figure it out. And I keep veering into looking at the C++ code to > try to figure it out and that way lies madness. :-) > > I'd be grateful for any hints. > > Thanks, > -Robert > > > > > > ------ ns-2 input file ----------- > > set ns [new Simulator] > set tf [open out.tr w] > $ns trace-all $tf > set nf [open out.nam w] > $ns namtrace-all $nf > > # Nodes and link > > set n0 [$ns node] > set n1 [$ns node] > > $ns duplex-link $n0 $n1 2.0Mb 100ms DropTail > $ns duplex-link-op $n0 $n1 orient right > $ns queue-limit $n0 $n1 20 > > # TCP agent connection > > set tcp0 [new Agent/TCP] > $ns attach-agent $n0 $tcp0 > > set sink0 [new Agent/TCPSink] > $ns attach-agent $n1 $sink0 > > $ns connect $tcp0 $sink0 > > # FTP application over TCP connection. > > set ftp0 [new Application/FTP] > $ftp0 attach-agent $tcp0 > > # 'Finish' proc. > > proc Finish {} { > global nf ns tf > close $tf > close $nf > exec nam out.nam & > exit 0 > } > > # Event sequence > > $ns at 0.5 "$ftp0 produce 1" > $ns at 10.0 "Finish" > > $ns run