On Fri, 2026-03-13 at 20:03 -0400, Robert Heller wrote: > I don't think anyone uses telnet for it *original* purpose. > > It is useful for *debuging* a Tcp/Ip server, since telnet can take a > port number as a parameter. That is, suppose you write a server > listening on port 12021, one can test the program with the command > > telnet localhost 12021 > > And then type what you would expect a client for your server would > send and see if the server responds properly.
You should never ever abuse 'telnet' for that purpose, as it is not a clean socket connection but a protocol with commands of its own (as the security issue mentioned earlier in this thread illustrates). You should use something like 'netcat' (often abbreviated as 'nc') or 'ncat' instead: nc localhost 12021 ncat localhost 12021 -- Jan Claeys (please don't CC me when replying to the list)
