prompt protocol

TF will recognize the TELNET protocol commands GOAHEAD or END-OF-RECORD as the end of a prompt. If you are responsible for a server that has prompts, and wish to make it more friendly to TF users, choose one of these options:

GOAHEAD: Send IAC GA (\377 \371) after each prompt. This is the easier of the two options. In many servers, this can be done at the beginning of the routine that reads user input. Disadvantage: could possibly cause problems in clients that don't understand TELNET protocol (but usually, they will just pass it through to the terminal, which will usually ignore it).

END-OF-RECORD: Send IAC WILL EOR (\377 \373 \031) when the user connects. If the client responds with IAC DO EOR, then you can send IAC END-OF-RECORD (\377 \357) after each prompt; otherwise, do nothing special in prompts. Disadvantage: requires extra state per descriptor and more understanding of telnet protocol. Advantage: minimizes potential problems for clients that do not recognize telnet protocol.

To debug telnet option negotiations, you may find it useful to "/set telopt on" in TF.

For more information on TELNET protocol, see RFCs 854, 855, 885, and 1123.

See also: /telnet, telopt, prompts, protocols


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