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c#protocolstelnet

Telnet server -> backspace/delete not working

I'm implementing a simple proof of concept Telnet server in C# and telnet to it via the windows built in telnet client. I echo all non IAC data back to the client. However, I can't figure out how to get backspace/delete to work correctly. I tried several combinations acting on 'BS' from the telnet client:

  • 'BS' (moves cursor back by one but doesn't delete character)
  • 'BS''DEL' (same result as 'BS' only)
  • 'BS''DEL''ESC[3~' (same result)

Can anyone please point me to what's the correct control sequence to backspace and remove the character from the screen?

Thanks,

Tom

Solution

  • I just connected to a Cisco switch and traced how IOS is implementing it. IOS is sending 'BS' 'SPACE' 'BS' on an incoming 'BS' from the client. So, that's how I implemented it now and works great.