[root@tron root]# lsof -i:80
COMMAND   PID USER   FD   TYPE DEVICE SIZE NODE NAME
httpd    2222 root    3u  IPv4   4336       TCP *kh
httpd    7419 root    3u  IPv4   4336       TCP *:http (LISTEN)
httpd   14385 root    3u  IPv4   4336       TCP *:http (LISTEN)
[root@tron root]#