From owner-freebsd-questions Mon Jan 19 22:27:29 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id WAA07454 for questions-outgoing; Mon, 19 Jan 1998 22:27:29 -0800 (PST) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from glitnir.cfar.umd.edu (root@glitnir.cfar.umd.edu [128.8.132.40]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id WAA07448 for ; Mon, 19 Jan 1998 22:27:20 -0800 (PST) (envelope-from arensb@cfar.umd.edu) Received: from cfar.umd.edu (arensb@localhost [127.0.0.1]) by glitnir.cfar.umd.edu (8.8.5/8.8.4) with ESMTP id BAA01330; Tue, 20 Jan 1998 01:15:00 -0500 (EST) Message-Id: <199801200615.BAA01330@glitnir.cfar.umd.edu> To: jak@cetlink.net (John Kelly) cc: questions@FreeBSD.ORG Subject: Re: What's a pseudo terminal? In-reply-to: Your message of "Mon, 19 Jan 1998 13:25:34 GMT." <34c353b6.473453@mail.cetlink.net> Date: Tue, 20 Jan 1998 01:15:00 -0500 From: Andrew Arensburger Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk On Mon, 19 Jan 1998 13:25:34 GMT, John Kelly wrote: > What is the use and/or purpose of a pseudo terminal? [Historical rant mode=ON] Way back when, in the mists of time, computers were big clunky boxes the size of several cabinets. Networks were an interesting theoretical notion that might one day become feasible. You logged in through a terminal, which was plugged in to a serial port on the back of the computer. At some point, people decided that it would be really keen if you could _pretend_ that a certain process was connected to a plain serial-line terminal, even when it wasn't. For instance, when you open an xterm window, it's convenient to pretend that you just hooked up a new terminal to a serial port. That's where pseudo-terminals come in. They're not terminals, but they act like them. -- Andrew Arensburger, Systems guy Center for Automation Research arensb@cfar.umd.edu University of Maryland AIDS is killing our Vampire population.