Bash/nc: netcat as a simple ftp server

gistfile1.txt

DATA TRANSFER
     The example in the previous section can be expanded to build a basic data transfer model.  Any information input into one end of the connection will be output to the other end, and input and output can be easily captured in order to emulate file trans‐
     fer.

     Start by using nc to listen on a specific port, with output captured into a file:

           $ nc -l 1234 > filename.out

     Using a second machine, connect to the listening nc process, feeding it the file which is to be transferred:

           $ nc host.example.com 1234 < filename.in

     After the file has been transferred, the connection will close automatically.