~ # nc -l 12345 &
~ # echo "Hello World" | nc localhost 12345
nc: can't connect to remote host (127.0.0.1): Connection refused
~ # ps
  PID USER       VSZ STAT COMMAND
    1 root      2880 S    init
    2 root         0 SW   [kthreadd]
    3 root         0 SW   [ksoftirqd/0]
<snip>
 1166 root      2880 S    nc -l 12345