[Sanddancer]

Seems more like an inetd to me. Give a command and run it again and again.

[joewalnes]

It's similar to netcat -e and inetd, except it also handles the WebSocket protocol (negotiating the handshake and message framing), so your apps don't need to.

[sgt]

If you're on Ubuntu (and maybe other distros as well), be sure to install the nc-traditional package. Otherwise you don't get the nifty features such as -e