Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!think!barmar From: barmar@think.COM (Barry Margolin) Newsgroups: comp.protocols.tcp-ip Subject: Re: telnet CR processing, bridge comm servers and TWG telnet Message-ID: <7419@think.UUCP> Date: Mon, 10-Aug-87 17:35:19 EDT Article-I.D.: think.7419 Posted: Mon Aug 10 17:35:19 1987 Date-Received: Tue, 11-Aug-87 06:46:15 EDT References: <27@abvax.icd.ab.com> <109@quick.UUCP> Sender: news@think.UUCP Reply-To: barmar@godot.think.com.UUCP (Barry Margolin) Organization: Thinking Machines Corporation, Cambridge, MA Lines: 38 Keywords: telnet TWG Bridge BSD4.3 In article <109@quick.UUCP> srg@quick.UUCP (Spencer Garrett) writes: > You hit > The Bridge box sends \r\n You said this twice in your message without justifying it. The key is labeled RETURN, which is generally taken to be a synonym for CR. The TELNET spec says that CR should be represented in NETASCII as CRNUL. Why should the Bridge box assume that CR is NEWLINE? > telnetd converts \r\n to \n and feeds it to the pty > telnet reads \n from its tty (pseudo-tty, but it shouldn't matter) > telnet sends \r\n through its tcp stream to the vax > the vax should convert \r\n to whatever it wants for EOL What if the program on the VAX wants to see the raw characters that the user typed, which happens in programs such as EMACS? This means that if the user types CR it will get translated into the VAX's EOL sequence, and the program may not see the CR that the user typed. Your scenario only works if the remote system is in line-at-a-time mode. The reason for all the confusion that the TELNET spec has caused is that NETASCII is used for more than terminal emulation. It is used in FTP, for example, to support the control connection and text-mode file transfers. In these cases, things like End-of-Line have much more obvious meaning, or at least the need for a standard representation is obvious (some systems use a character sequence to indicate newline, others use a record structure). In terminal emulation, whether the RETURN key indicates End-of-Line is totally context dependent. In EMACS I can map any key to any operation, and I don't want the network to transform my keyboard for me. --- Barry Margolin Thinking Machines Corp. barmar@think.com seismo!think!barmar