page@ulowell.UUCP (11/27/86)
When I use some escape sequences to move the cursor (like CSInD to move the cursor back n spaces), the cursor moves across line boundaries like you would expect. For example, if I want to move across a word that is split between lines because the end of the window cuts it, it will do so correctly. However, the delete character (CSInP) command does not cross line boundaries. In fact, if I'm at column 70 of 77 and say 'CSI10P' to delete 10 characters, it deletes the first 8 (70 through 77) as expected but then instead of deleting 0, 1 and 2 of the next line, it deletes 69, 68 and 67 of the same line! Is this a bug, or a feature? I would say a bug, since the whole idea of 'console' device is that it is a virtual terminal, and the program should not have to constantly worry about what size the window is. Sigh. My only regret (besides the fact that now I have to write code to emulate what the console.device should be doing) is that I just found this, and two months ago it might have been fixed in time for V1.2. ..Bob PS All references to 'CSI' mean hex 9b, the Control Sequence Introducer. PPS I am using 1.2 (KS 33.180). -- Bob Page, U of Lowell CS Dept. ulowell!page, page@ulowell.CSNET
andy@cbmvax.cbm.UUCP (Andy Finkel) (12/03/86)
In article <791@ulowell.UUCP> page@ulowell.UUCP (Bob Page) writes: >When I use some escape sequences to move the cursor (like CSInD to move >the cursor back n spaces), the cursor moves across line boundaries like >you would expect. For example, if I want to move across a word that is >split between lines because the end of the window cuts it, it will do >so correctly. > >However, the delete character (CSInP) command does not cross line >boundaries. In fact, if I'm at column 70 of 77 and say 'CSI10P' to >delete 10 characters, it deletes the first 8 (70 through 77) as expected >but then instead of deleting 0, 1 and 2 of the next line, it deletes >69, 68 and 67 of the same line! > >Is this a bug, or a feature? I would say a bug, since the whole idea >of 'console' device is that it is a virtual terminal, and the program >should not have to constantly worry about what size the window is. > There are actually 2 bugs here...the first is that the cursor moves across line boundaries, when moved with the cursor commands. According to my VT101, this is wrong. The second is the way it deletes when it hits the end of line. As you noticed, it then deletes too much. >Sigh. My only regret (besides the fact that now I have to write >code to emulate what the console.device should be doing) is that I >just found this, and two months ago it might have been fixed in time >for V1.2. > me too. (sigh) >..Bob andy finkel -- andy finkel Commodore/Amiga {ihnp4|seismo|allegra}!cbmvax!andy or pyramid!amiga!andy Any expressed opinions are mine; but feel free to share. I disclaim all responsibilities, all shapes, all sizes, all colors. "Never make anything simple and efficient when it can be complex and wonderful."