Path: utzoo!attcan!uunet!wuarchive!cs.utexas.edu!radar!duanev
From: duanev@radar.ACA.MCC.COM (Duane Voth)
Newsgroups: comp.windows.x
Subject: Re: rlogin and the DISPLAY variable
Summary: overload $term
Message-ID: <1340@kauai.ACA.MCC.COM>
Date: 18 Oct 90 21:15:35 GMT
References: <m0iOhip-00013UC@aleytys.uu.net>
Organization: MCC ACT Program, Austin, TX
Lines: 48

In article <m0iOhip-00013UC@aleytys.uu.net>, mike%aleytys@UUNET.UU.NET (Michael Kent) writes:
> I need to rlogin to a remote X Workstation from my local X Workstation,
> and have the DISPLAY environmental variable properly...
>
> Having the user's profile
> set DISPLAY is out, as the user can be logging in from several different
> local machines.

I've successfully been overloading $term.  I can start from any machine,
rlogin as far as I want, and the new shell will always set $DISPLAY
to the machine I started from.  This works fine so long as
all target accounts contain .cshrc code to reset $TERM before
it is used for anything.  If you are a sysop this shouldn't be a problem.
Sorry, sh/ksh/bash users, I've not tried this with other shells.

Here are the useful parts of a .cshrc:
--------------------

if ( "$term" =~ *%* ) then              # check for special variables
        eval `echo $term | sed '/[0-9A-Za-z]*%/s///'`
        set term=`echo $term | sed '/%.*/s///'`
endif

alias   _to     'set term=${term}%\!*'


if ($term == "xterm") then
        if ($?RDISPLAY) then
                if ( "$RDISPLAY" =~ ${hostname}* ) then
                        setenv DISPLAY unix:0
                else
                        setenv DISPLAY $RDISPLAY
                        echo "remote display $RDISPLAY"
                endif
        else
                setenv DISPLAY unix:0
                setenv RDISPLAY ${hostname}:0
        endif

        alias rlogin    '(_to "setenv RDISPLAY $RDISPLAY"; /usr/ucb/rlogin \!*)'
endif

--------------------
-- 
--- duane voth                                         duanev@mcc.com
----    {uunet,harvard,gatech,pyramid}!cs.utexas.edu!milano!pp!duanev
--- ALL systems are arbitrary!  Effectiveness is the measure of Truth
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