Dropped into the comments to mention socat. I use it regularly to debug serial and multicast issues or to lash up network logging for random shell scripts. It's

Dropped into the comments to mention socat. I use it regularly to debug serial and multicast issues or to lash up network logging for random shell scripts. It's a very valuable addition to the toolbox IMO. Edit: somehow my phone managed to post this comment three times. I've deleted the others