Continuously listen on a port and respond with a fixed message with netcat (and respond to kill signals)

while true ; do nc -l -p 4300 -c 'echo hello'; test $? -gt 0 && break; done
`while true`: do forever `nc -l -p 4300 -c 'echo hello'`: this is the but anything can go here really `test $? -gt 0 && break`: this checks the return code for ctrl^c or the like and quite the loop, otherwise in order to kill the loop you'd have to get the parent process id and kill it.
Sample Output
Terminal 1% while true ; do nc -l -p 4300 -c 'echo hello'; test $? -gt 0 && break; done

Terminal 2% echo hi | nc localhost 4300
hello
Terminal 2% echo hi | nc localhost 4300
hello

Terminal 1% ^C
Terminal 1%

0
By: rawco
2016-03-22 21:55:44

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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