The netcat tool nc can operate as a TCP client.Because HTTP works over TCP, nc can be used as an HTTP server!Because nc is a UNIX tool,we can use it to make custom web servers:servers which return any HTTP headers you want,servers which return the response very slowly,servers which return invalid HTTP,etc.You can also use nc as a quick-and-dirty static file server.
Here’s an example.Run your web server bytelling nc to listen for new connections on port 8000:
Once you start typing the HTML,you’ll see it come line-by-line in your curl command.When you’ve finished typing the HTTP response,hit Ctrl-D.This tells nc to close the TCP connection and exit.The server is no more!
To run a persistent static server without typing anything in,write your HTTP response to a file like index.http:
See Also
10 Useful nc (ncat) Command Examples for Linux Systems8 Netcat “nc” Command Examples on Linux / Ubuntu8 Practical Linux Netcat NC Command Examplesnc: arbitrary TCP and UDP connections and listens - Linux Manuals (1)As an example of a “weird web server” you can make with nc,you can simulate a very slow web server.Use pv --rate-limit 10 to read the file at 10 bytes per second:
Tagged #programming, #unix, #networking.
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