What process is using what port?

Method 1

# ps -ef | grep sendmail
    root   197     1  0 14:22:31 ?        0:00 /usr/lib/sendmail -bd -q15m
    smmsp  198     1  0 14:22:31 ?        0:00 /usr/lib/sendmail -Ac -q15m

# pfiles /proc/197 | grep port
    sockname: AF_INET 0.0.0.0  port: 25
    sockname: AF_INET6 ::  port: 25

Method 2

# lsof -i TCP:25
  COMMAND  PID USER   FD   TYPE        DEVICE SIZE/OFF NODE NAME
  sendmail 197 root    5u  IPv4 0x30000a981b8      0t0  TCP *:smtp (LISTEN)
  sendmail 197 root    6u  IPv6 0x30000a98338      0t0  TCP *:smtp (LISTEN)