Aucbvax.5890 fa.info-vax utcsrgv!utzoo!decvax!ucbvax!info-vax Thu Jan 21 08:22:06 1982 Re: UNIX vs. VMS >From Samuelson@SANDIA Thu Jan 21 08:19:31 1982 While I agree with you that systems should allow programs to take characters from the terminal with no funny side effects at times, it is certainly not true that they should ALWAYS do that. I think an intelligent terminal handler should be part of an operating system. The "pause at end of page" handling done by TOPS-20 is a good example of something the operating system SHOULD do FOR the user. It can be turned off, so if you are not interested it will not do it TO you. That is a very important distinction. I have never seen any text editor which did not have some special characters which distinguish text from commands, and escape is a very reasonable character to make that distinction. The problem is to include some convenient way to allow special characters to be treated as text. EMACS does that in a remarkably simple way, using control-q to mean "quote the next charcter" or "treat the next character as text, no matter what it normally does". On output it is perfectly reasonable for the system to do special things with such characters as form-feed. The problem is to make the system smart enough that it will do what is right for your terminal. Some terminals clear the screen on a form-feed, for example. You may NOT want the form-feed sent immediately after the text on such a terminal, but rather held till you can read the text, or possibly turned into some number of line feeds. The choice should be up to the user, the system should not force any particular arbitrary choice, including doing nothing. What I am saying is that neither UNIX nor VMS is doing it right! The action that the operating system takes with special characters sent to the terminal should be kept flexible, with the user allowed to specify easily what is to be done with special characters on both input and output! - Sam - ------- ----------------------------------------------------------------- gopher://quux.org/ conversion by John Goerzen of http://communication.ucsd.edu/A-News/ This Usenet Oldnews Archive article may be copied and distributed freely, provided: 1. There is no money collected for the text(s) of the articles. 2. The following notice remains appended to each copy: The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996 Bruce Jones, Henry Spencer, David Wiseman.