I have to develop a client for a proprietary protocol and it would be very useful to be able to understand the behaviour of the existing server by sending it custom messages and look at the answer. "Telnet" would be perfect for that purpose except that the protocol is binary.
So currently, I have written the message i want (using a hex editor) in a file
mymsg and I'm trying to send it using netcat this way:
cat msg | netcat 127.0.0.1 1234
My problem with that is that netcat just stops after it reaches EOF so I never get to see the answer of the server. Any suggestions?
(of course, one can run a mock-up of the proprietary server using
nc -l -p 1234)