<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Type" content="text/html;charset=ISO-8859-1"> <title></title> </head> <body> Neil W. Van Dyke wrote: <blockquote type="cite" cite="mid16093.56394.200680.319186@neilvandyke.org"> <pre wrap=""> For list-related administrative tasks: <a class="moz-txt-link-freetext" href="http://list.cs.brown.edu/mailman/listinfo/plt-scheme">http://list.cs.brown.edu/mailman/listinfo/plt-scheme</a> Chris <a class="moz-txt-link-rfc2396E" href="mailto:chris81@wanadoo.fr"><chris81@wanadoo.fr></a> writes at 12:13 04-Jun-2003 +0200: </pre> <blockquote type="cite"> <pre wrap="">I just want to know if a client telnet made in scheme allready exist and </pre> </blockquote> <pre wrap=""> One might exist (I don't know), but writing your own is a really good learning exercise. </pre> <blockquote type="cite"> <pre wrap="">and it's send me nothing back but i see the connexion opened in the telnetd log. Am I missing something ? </pre> </blockquote> <pre wrap=""> Perhaps the Telnet server is not sending a full line; for example, maybe it's just sending "Password: " without a newline sequence. Or maybe it's using a nonstandard newline convention, like CR (PLT's "read-line" can be made to handle this, but there's a better way). Instead of using "read-line", you probably want your code to read single characters or blocks of characters, rather than waiting for the server to send a newline. You will need this for other parts of the protocol anyway. Here's a simple variation on the code you posted: (display "*DEBUG* Connecting...\n") (define-values (p-in p-out) (tcp-connect "host" 23)) (display "*DEBUG* Connected.\n") (let loop () (display "*DEBUG* Waiting for character...\n") (let ((c (read-char p-in))) (printf "*DEBUG* Read character: ~S\n" c) (loop))) If this code doesn't read any characters from your Telnet server, then it could be waiting for the client to send one or more newlines or it could be waiting for the client to initiate a cryptographic authentication. Don't think too hard about "*DEBUG*" messages that aren't appearing, since they might be stuck in unflushed I/O buffers. Try running a protocol sniffer or packet analyzer, like the free Ethereal, while you connect to your Telnet server with your system's Telnet client, to see how it works. Once you can read and write single characters with your Telnet server, take a look at the PLT procedures "read-string-avail!/enable-break" and "write-string-avail/enable-break", and "object-wait-multiple" for how to do this robustly and more efficiently. Searching for "telnet" from <a class="moz-txt-link-rfc2396E" href="http://www.rfc-editor.org/rfcsearch.html">"http://www.rfc-editor.org/rfcsearch.html"</a> yields over 100 documents, most of which are not relevant to you. RFC 318 (<a class="moz-txt-link-rfc2396E" href="ftp://ftp.rfc-editor.org/in-notes/rfc318.txt">"ftp://ftp.rfc-editor.org/in-notes/rfc318.txt"</a>) might be a good starting point. </pre> </blockquote> I once wrote me a little telnet client. If you want it, there's a file attached. By the way, if anyone can figure out why this programs slows down the more you use it, I'd appreciate it. Yours truly, Katsmall T. Wise, Esquire. </body> </html>