Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/5/84; site yojna1.UUCP Path: utzoo!watmath!clyde!burl!ulysses!allegra!mit-eddie!think!harvard!seismo!umcp-cs!aplcen!cp1!yojna1!wb6rqn From: wb6rqn@yojna1.UUCP (Brian Lloyd) Newsgroups: net.unix Subject: Re: Re: Info needed on pseudo TTYs in SysV Message-ID: <132@yojna1.UUCP> Date: Wed, 13-Nov-85 14:15:24 EST Article-I.D.: yojna1.132 Posted: Wed Nov 13 14:15:24 1985 Date-Received: Sat, 16-Nov-85 09:52:33 EST References: <3073@brl-tgr.ARPA> Organization: Yojna1 Amateur Radio Packet Unix System; Germantown, Md. Lines: 19 > Actually, the way the System V terminal driver is set up, it is > designed to help you do this. Unfortunately, it means driver > hacking, and you really do need a UNIX source license. If you > can find one, look at the xt.c driver for running the BLITs and > tty5620 terminals, it is switching a packetized input stream > consisting of six virtual terminals into separate xt000 devices. > > System V doesn't really have pty's at all. The SXT (which are VR2 > anyhow) devices are a kludged up version of the code for the xt > driver. What they do is switch a single real tty line back and > forth between a set of virtual terminals. Doing this, they achieve > something roughly equivelent to the 4.2 Job control. The difference > is that you actually have a shell on each of the sxt virtual devices. > What you are really doing is switching your real tty to several virtual > tty "contexts." > > -Ron *** REPLACE THIS LINE WITH YOUR MESSAGE ***