> The Unix solution is netstat.  Ask netstat for all listening connections
> like this:
> $ netstat -a | grep LISTEN

Since unix treats everything as a file, you could also use lsof like this:

$ lsof -i
COMMAND  PID USER   FD   TYPE DEVICE SIZE NODE NAME
ntpd     183 root    4u  IPv4    274       UDP *:ntp
ntpd     183 root    5u  IPv4    275       UDP localhost:ntp
ntpd     183 root    6u  IPv4    276       UDP 192.168.1.149:ntp
inetd   4603 root    4u  IPv4  26225       UDP *:amanda
inetd   4603 root    5u  IPv4  26226       TCP *:amandaidx (LISTEN)
inetd   4603 root    6u  IPv4  26227       TCP *:amidxtape (LISTEN)
proftpd 4627 root    0u  IPv4  26367       TCP *:ftp (LISTEN)
exim    4653 root    0u  IPv4  26384       TCP localhost:smtp (LISTEN)
sshd    9013 root    3u  IPv4  37451       TCP *:ssh (LISTEN)
sshd    9022 root    4u  IPv4  37477       TCP 
redstone.somewhere.com:ssh->192.168.1.185:4053 (ESTABLISHED)


-- 
Chris Lewis
shadow@digitalnirvana.com
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If it compiles, it is good, if it boots up it is perfect.
       - Linus Torvalds
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