lsof and listening ports

Question

I am trying to get all the processes listening for a network connection on Mac OS X. netstat does not have the -p option and I am trying with lsof

lsof -i -sTCP:LISTEN

gives me a fair list of listening processes but not all. I can for example telnet to port 10080 where I have a process listening for a connection but this is not shown in the output of lsof. What am I missing?

$ telnet localhost 10080
Trying ::1...
Connected to localhost.
Escape character is '^]'.
^]
telnet> Connection closed.

but

$ sudo lsof -n -i | grep 10080
$

Answer 1

sudo lsof -iTCP -sTCP:LISTEN

sudo lsof -iTCP -sTCP:LISTEN -P

sudo lsof -iTCP -sTCP:LISTEN -P -n

sudo lsof -iTCP -sTCP:LISTEN -n

All return the same 32 entries (... | wc -l) on my heavily used Lion MBP.

-P -n prevents lsof from doing name resolution, and it doesn't block. Missing either one of these, it can be very slow.

For UDP: sudo lsof -iUDP -P -n | egrep -v '(127|::1)'. Without -n and -P, it takes a long time.

Reminder: This does not include firewall settings.