Help, I want to get the host name who sent me a message

[PAD Powell [Admin]]

<munch>
I have been trying to find a way to set up the networking data base
to allow me to get a "unique" host name.  The problem is the following.

We have two networks, mathnet (1) and async (2)  [Forget the numbers,
they are changed to make life easy].  The host "watmath" is on both
networks, and the /etc/hosts file looks like:

1.1	watmath
1.2	watdaisy

2.1	watmath-x
2.2	wateng

To start up the network, watmath has an entry in the /etc/rc.local file
/etc/ifconfig eu0 watmath
/etc/ifconfig ttif0 watmath-x

Similarly, wateng has an entry
/etc/ifconfig ttif0 wateng
/etc/route add mathnet watmath-x 1

This procedure has the following interesting property:
all messages from watmath arriving at wateng are tagged as coming from
watmath-x;  this is the result returned by "gethostbyname(3n)",
in the h_name field.

What I would like to do is assign an "official name" to watmath,
which would always be returned by "gethostbyname(3n)".  In addition,
I would like to be able to use this name for naming the host.  My first
thought was to change watmath-x to watmath, and leave it at that;
this would cause conflicts in names.  It seems to me that there should be
a way to do this;  I cannot find an example, and am a little leary of
experimenting.

Secondly, is the /etc/route line neccessary?  If it is, can an entry in
/etc/gateways be used instead?  and if it can, what is the format?

Finally,  can anybody explain or give a pointer to a written explanation of the
relationship between the files /etc/hosts, /etc/networks, and so forth,
and the programs or operating system parts that use them?  I have read the
implementation document, but am still a little puzzled.

Patrick Powell
VLSI Research Group, U. Waterloo