Netcat is something of a Swiss Army knife of a networking tool – it’s
remarkably handy for doing things like creating minimal TCP clients and servers
for development purposes. What I didn’t realize was that netcat can also
communicate via UDP. To, for example, send a UDP message to a server listening
for UDP traffic on port 3333,
you could run:
$ echo "This is a UDP message" | nc -cu 127.0.0.1 3333
This will send “This is a UDP message” over UDP and include a CRLF line-ending. This has been particularly handy as a quick way to interact with UDP services.