Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site umcp-cs.UUCP Path: utzoo!linus!philabs!seismo!rlgvax!cvl!umcp-cs!chris From: chris@umcp-cs.UUCP Newsgroups: net.emacs Subject: Re: EMACS vs. reverse video Message-ID: <3505@umcp-cs.UUCP> Date: Tue, 1-Nov-83 12:22:47 EST Article-I.D.: umcp-cs.3505 Posted: Tue Nov 1 12:22:47 1983 Date-Received: Fri, 4-Nov-83 02:04:49 EST References: <6020@cca.UUCP> Organization: Univ. of Maryland, Computer Science Dept. Lines: 41 On the :xs: type terminals with which I have had experience (Tek 4025 in workspace & HP 262x/264x) inserting a character *does* push the attribute over in the screen. The Tek (and probably the HP) uses something called a "display tracker" which wanders through screen memory, interpreting special codes. One of these is for "start enhancement mode ". When you insert a character, the insertion moves the "start enhancement" code one space to the right, moving the attribute on the screen. Also, (again at least on the Tek & HP) you can get rid of the highlighting without using clear to end of line. Just write a new highlight code at the same position as the old one. This is how my windows driver for HPs works. The easiest way to get around the Televideo type "magic cookie" glitch is (as Steve Zimmerman said) to not use standout. However, it is possible to deal with this kind of inverse video, as long as you aren't trying to mix inverse video and normal characters on the same line, by noting that one or two "spaces" are there and that cursor motion must be adjusted, and that the line is shorter than it would be normally. (If you're in the market for terminals, beware the magic cookie type. There's an Intel display controller (I can't remember which one) which seems to be the major reason for the existence of the magic cookie glitch.) (Speaking of glitches: the 4025 also has codes for "no-op" and "anti-no-op" and jump instructions. It's very easy to load up enough JUMP instructions to get the display all screwed up because the tracker can't keep up. If you get the long sequence behind a NOP or ANOP the screen starts to bounce up and down. If you're on a 4025, try ( = return): !wor 10 h!att e-sa!att s-eb!att e-sc!att s-ed (etc) With enough of those the screen will start to jiggle about and you may get cursors on every line. Fun, eh?) -- In-Real-Life: Chris Torek, Univ of MD Comp Sci UUCP: {seismo,allegra,brl-bmd}!umcp-cs!chris CSNet: chris@umcp-cs ARPA: chris.umcp-cs@CSNet-Relay