Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!usc!zaphod.mps.ohio-state.edu!wuarchive!decwrl!ucbvax!EN.ECN.PURDUE.EDU!stevew
From: stevew@EN.ECN.PURDUE.EDU (Steven L Wootton)
Newsgroups: comp.unix.questions
Subject: Same i/o on two terminals?
Message-ID: <9002110817.AA06477@en.ecn.purdue.edu>
Date: 11 Feb 90 08:17:23 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 26


Say I log in to my account from two different physical terminals.  Each
login process gets its own /dev/tty* (of course).  I'll call them terminals
A and B (so I won't confuse myself).

Is there any way that I use terminal B to control the process running on
terminal A?  That is, can I get the same i/o on both screens at the same
time?  The implication here is that I want the same characters to echo on
each terminal.

I can see why this might be a "bad thing" from a security standpoint, but I
can't see why this should be an issue if I only do this from one of my
logins to another.

My site specialist didn't have any information on this.

The systems I use most include a Gould NP1 (4.2 BSD), an HP 9000/300 (HP-UX
[SVR3]), and an Amdahl of some sort (UTS [SVR3]).

Any shell scripts, C code fragments, RTFM pointers, or explanations as to
why this is impossible are appreciated.  Email is fine as well.  Thanks.

Steve Wootton
stevew@{en,ei,el}.ecn.purdue.edu
stevew@pur-ee.uucp
stevew%ecn.purdue.edu@purccvm.bitnet