From: Peter Eriksson (pen@lysator.liu.se)
Date: 02/14/93


From: pen@lysator.liu.se (Peter Eriksson)
Subject: Announce: rwhod et al for Linux available
Date: 14 Feb 1993 13:27:34 GMT

I've written an "rwhod" daemon for Linux that uses the /proc filesystem.
You can get it from "ftp.lysator.liu.se:pub/linux/daemons" as the file
"rwhod-0.1.tar.Z". Included in the tar file is also the "rwho" and "ruptime"
programs from the 4.3BSD-reno distribution.

Below follows the README file.
======================================================================
This is rwhod version 0.1, my implementation of an rwhod daemon for
Linux 0.99.5 or later. Just type "make" in this directory to build it.

Included is also the "ruptime" and "rwho" clients from the BSD
distribution.

I can't seem to get UDP broadcasting to work on our box (running Linux
0.99.5) here, and it's getting late now so that will have to wait for
some other time.

Command line options:

   -t[<target-address>] Send UDP messages to the specified host.
                                If <target-address> is omitted, use UDP
                                broadcasts on the local ethernet. Multiple
                                targets are allowed.

   -s[<source-address>] Listen to incoming UDP messages from the
                                specified <source-address>. If it is
                                omitted, listen to all incoming messages
                                (ie, broadcasts also). Multiple sources
                                are possible.

   -r<source-address> Act as an information relayer for the
                                Rwhod daemon running at <source-address>.
                                Multiple relaying sources are possible.

   -w<seconds> Time to wait before transmitting information
                                about ourself to the world

   -p<portnum> Port to use for the messages (both in and
                                outgoing)

   -d Don't detach from tty and (in the future)
                                enable some debugging output.

Currently you must specify the source and target addresses using dot (number)
notation. It doesn't yet grok hostnames. (See TODO). You also must use a number
for <portnum> and not the symbolic name in /etc/services.

Since there aren't any manual page for it yet I'll give some example on how to
use it below:

rwhod -t -s
   Behave just like normal "rwhod" daemons do. (For this to work someone will
   have to fix the kernel, or my code if the problem is in it and not the kernel,
   so that UDP broadcasting works :-)

rwhod -t193.180.23.1
   Only act as an information provider, sending information to the host at
   193.180.23.1 only. Do not collect information about other hosts. This is
   a useful mode if you have a sitewide rwho-collecting daemon which the
   other machines then access using NFS.

rwhod -t193.180.23.1 -t130.236.254.1
   Only act as an information provider, sending information to the hosts at
   193.180.23.1 and 130.236.254.1 only. Do not collect information about
   other hosts. This is a useful mode if you have a sitewide rwho-collecting
   daemon which the other machines then access using NFS.

rwhod -t -r193.180.23.2
   Broadcast information about the local host and any information received
   from the rwho daemon at host 193.180.23.2. This can be very useful to
   spread the information over a greater site if the site has a network
   consisting of a number of separated ethernets that broadcasts won't be
   able to reach all machines. (This requires that the rwhod at 193.180.23.2
   has the ability to send directed UDP messages like this one can).

Peter Eriksson, 14 Feb 1993

Email: pen@signum.se (Signum Support AB, Sweden)
Email: pen@lysator.liu.se (Lysator ACS, Linkoping University, Sweden)