From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (qmail 3181 invoked from network); 14 Dec 1998 06:03:26 -0000 Received: from mail.redhat.com (199.183.24.239) by lists.redhat.com with SMTP; 14 Dec 1998 06:03:26 -0000 Received: from ohio.river.org (river.org [209.24.233.15]) by mail.redhat.com (8.8.7/8.8.7) with ESMTP id AAA30850 for ; Mon, 14 Dec 1998 00:55:04 -0500 Received: (from ru@localhost) by ohio.river.org (8.8.8/8.7.3) id VAA29035; Sun, 13 Dec 1998 21:55:00 -0800 (PST) Date: Sun, 13 Dec 1998 21:55:00 -0800 (PST) Message-Id: <199812140555.VAA29035@ohio.river.org> From: Richard Uhtenwoldt To: blinux-list@redhat.com Subject: the glass tty model of human-computer interaction List-Id: I'm not blind, just interested in making my software blind friendly. In the Seventies before the personal computer became popular a lot of interaction with computers occured via the so-called hardcopy terminal, like the DECwriter and the Teletype Model 33 before that, which is essentially a keyboard connected to a printer. at the end of the session, you have a long piece of paper that is essentially a transcript of everything you wrote and everything the computer wrote in reply. there was also the dumb terminal, also called the glass tty, which differed from a vt100 in that its cursor was not addressible. the only way the computer could update a glass tty was by writing a line of text at the bottom of the screen and having whatever was on the screen scroll up one line. cursor-addressible terminals were also called smart terminals. now we may laugh at the idea, but in the Seventies a smart terminal cost thousands of dollars, hence the market for dumb terminals as a lower-cost solution. you could not use vi or Emacs on a hardcopy terminal or a glass tty. what you used instead was what I will call a "line editor" which had commands like "delete the next 5 lines" and "print the next 5 lines". the Unix command "ed" and I think also "ex" are line editors. sighted users came to prefer so-called visual editors like vi and Emacs in which most of the display is devoted to an alway-up-to-date view of the thing being edited. it occurs to me, tho, that if I were a blind user using text-to-speech hardware or a braille output device, I would prefer a line editor. but the Linux Access Howto mentions Emacspeak but does not mention any line editors. so, if you are blind and have used a line editor, please tell me whether you prefer line editors or visual editors.