Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: Notesfiles $Revision: 1.6.2.17 $; site smu.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxj!houxm!ihnp4!inuxc!pur-ee!uiucdcs!smu!pedz From: pedz@smu.UUCP Newsgroups: net.unix-wizards Subject: Call for Opionings Message-ID: <32300011@smu.UUCP> Date: Thu, 3-Jan-85 13:55:00 EST Article-I.D.: smu.32300011 Posted: Thu Jan 3 13:55:00 1985 Date-Received: Sat, 5-Jan-85 03:12:19 EST Lines: 41 Nf-ID: #N:smu:32300011:000:2048 Nf-From: smu!pedz Jan 3 12:55:00 1985 Two questions looking for your opionings. Please mail responses to me directly and I will post them. First: I get the general feeling that Berkeley is thinking about implementing (or perhaps has already done so) a virtual termianal system. I am not sure what they want to do but here is what I am thinking about doing. Basically take a termcap and curses type implementation and put them down into the kernel. Instead of making system calls, there would be a set of escape sequences which could be used to position the cursor, add lines, delete lines, insert characters, etc. These commands would be interpreted and then the real sequence of commands would be sent out by the kernels code. You are probably asking "why do this". Well, it would seem to me that it would utilize the physical memory better. If there is more than one program that uses some type of terminal cursor control package running at a particular time, then there is as many copies of the code to do cursor positioning in the memory someplace. There are also many advantages to this type of system. Basically since the code is already there, programmers would be much more likely to go ahead and do the proper things on the screen where in some cases, they simply dont bother. Also, such things as tabs and so forth could always be handeled properly. So the question is, what do you think about putting this much code into the kernel. Obviously this is only intended for computers with large physical memories. Second: I recently wrote a "more" type program with the added feature of being able to move forward and backward through the file. The first few versions of the program simply kept an index of the file and then did seeks when the person wanted to go backwards. The last version I wrote simply keeps all of the lines "in memory". Note that we have a Vax with virtual memory. Thus the question is, which is better: doing random accesses on a disk file or doing random accesses in the virtual memory swap space? Perry convex!smu!pedz pedz@smu (csnet)