setting REMOTEHOST on rlogins

[Bernard J. Duffy]

In article <1991Jun12.174725 at spruce.gsfc.nasa.gov> karl at spruce.gsfc.nasa.gov (karl anderson) writes:
>I'm just getting acquainted with SGI machines after using Suns alot.
>I see that when I rlogin to one of our Irises, an environment variable
>named "REMOTEHOST" is set to the name of the machine I'm logging in
>from.  Is this something unique to IRIX?  I'd love to be able to do 
>that on my Suns - can anyone tell me how?  Please answer by email,
>as I don't ordinarily take this group.  TIA.
    You can make a simple C program that could set this for you and
it would be pretty easy to port to most of your un*x-es .  I've noticed
that the who command on most machines states which host a terminal
or X session started a particular login.  I think most of the "login"
(like rlogin and telnet) programs / daemons provide this information.

The informat for the REMOTEHOST is held in the world readable /etc/utmp
that the who utility reads for you.  Your non-suid (non-prived) program
can scan /etc/utmp and extract the REMOTEHOST.  This would be of use
to X users because you can make various terminal settings based on
the originating host (like ^? for DEL when it's not a window on an
IRIS server).

>
>--
>Karl A. Anderson		| Internet: karl at forest.gsfc.nasa.gov
>NASA/GSFC code 923 (STX)	| voice: (301) 286-3815
>Greenbelt, MD 20771		| #include "std_disclaimer"

Have fun,   Bernie   bernie at pinhead.acs.umbc.edu

UMBC: the only University with "County" in its name...  that's why they
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