From owner-freebsd-hackers@FreeBSD.ORG Thu Aug 30 13:41:52 2007 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3BD9616A418 for ; Thu, 30 Aug 2007 13:41:52 +0000 (UTC) (envelope-from gahr@gahr.ch) Received: from cpanel03.rubas-s03.net (cpanel03.rubas-s03.net [195.182.222.73]) by mx1.freebsd.org (Postfix) with ESMTP id C2F4813C480 for ; Thu, 30 Aug 2007 13:41:51 +0000 (UTC) (envelope-from gahr@gahr.ch) Received: from deconet115-230.bfh.ch ([147.87.115.230] helo=gahrtop.localhost) by cpanel03.rubas-s03.net with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.63) (envelope-from ) id 1IQkGg-00082h-1E; Thu, 30 Aug 2007 15:41:06 +0200 Message-ID: <46D6C8EA.7000809@gahr.ch> Date: Thu, 30 Aug 2007 15:40:58 +0200 From: Pietro Cerutti User-Agent: Thunderbird 2.0.0.6 (X11/20070808) MIME-Version: 1.0 To: djembe nazar , freebsd-hackers@freebsd.org References: In-Reply-To: X-Enigmail-Version: 0.95.2 OpenPGP: id=9571F78E; url=http://www.gahr.ch/pgp Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="------------enig4FE0FA4EEF7A483B8C6A1CE6" X-Antivirus-Scanner: Clean mail though you should still use an Antivirus X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cpanel03.rubas-s03.net X-AntiAbuse: Original Domain - freebsd.org X-AntiAbuse: Originator/Caller UID/GID - [0 0] / [47 12] X-AntiAbuse: Sender Address Domain - gahr.ch X-Source: X-Source-Args: X-Source-Dir: Cc: Subject: Re: two-way terminal multiplexing X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 30 Aug 2007 13:41:52 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig4FE0FA4EEF7A483B8C6A1CE6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable djembe nazar wrote: > I am trying to work out a way to do the following for a > "FreeBSD teaching environment": >=20 > The intention is to have two terminals, one above the other. > The bottom terminal shows one's own commands and output like > an ordinary xterm whilst the top terminal shows the commands > and output of a peer (such as an instructor). >=20 > The pupil is not allowed to enter commands into the > instructor's terminal, it simply shows what the instructor > typed and the resulting output of the commands. The same > is true of the reverse. The overall concept is to allow an > instructor to tutor a pupil over an appropriate medium such > as instant messaging whilst allowing the pupil to learn by > example with a very hands-on approach. >=20 > In the case of a standard 1-to-1 teaching environment, the > instructor would see his/her own terminal on the bottom and > the terminal of the pupil on the top. The pupil would see the > reverse (instructor's terminal above, his/her own terminal > below). >=20 > pupil sees: instructor sees: > +-----------------+ +-----------------+ > | INSTRUCTOR TERM | | PUPIL TERM | > +-----------------+ +-----------------+ > | PUPIL TERM | | INSTRUCTOR TERM | > +-----------------+ +-----------------+ >=20 > I do not understand how to achieve this. Is this even possible > given standard unix security with regards to hijacking the > tty devices of other users on the system? A solution would be to use a combination of GNU screen(1) [sysutils/screen] and watch(8) [in the base system]. Screen would be used to multiplex a terminal in two upper and lower regions, with watch would be used to see the output of another terminal. I never used it on remote terminals, but you could solve the problem by letting both the teacher and the pupil connect to a common remote machine, say lecture-machine. Once connected (via SSH), both would use screen(1) to create two pseudo multiplexed terminals, e.g.: piter p3 :0:S.0 3:38PM - /bin/tcsh piter p4 :0:S.1 3:38PM - /bin/tcsh It would then suffice for both to open watch(8) and watch on one of each other's screen pseudo terminals. (not tested)... Hope this helps, >=20 > -- > D.N > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.o= rg" --=20 Pietro Cerutti PGP Public Key: http://gahr.ch/pgp --------------enig4FE0FA4EEF7A483B8C6A1CE6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (FreeBSD) iD8DBQFG1sjuwMJqmJVx944RCsENAJ43umK3sl+Tx8TM396ZCypL++6u6gCgjvt9 HTtYQHWgzwY1hFidesrf0+s= =znLu -----END PGP SIGNATURE----- --------------enig4FE0FA4EEF7A483B8C6A1CE6--