unix rwho

[Brad Miller <miller@doughnut.cs.rochester.edu>]

    Date: Thu, 10 Sep 87 14:48:43 EDT
    From: royt@pravda.gatech.edu (Roy M Turner)


    I was looking over the documentation and noticed that the Symbolics
    supports something called unix-rwho service; however, upon looking it
    up in the TCP code, I didn't see that it really *did* anything except 
    intercept rwho packets from unix hosts and store them in a variable.
    Does anyone have any functions to make use of this information, such
    as something that will do the equivalent of unix's rwho command?  Or 
    even better, a replacement server that will send information back to 
    Unix's rwho server, so that information about the lisp machines show
    up in rwho's done on unix?

    Thanks.

    Roy

About a year ago I started to do something like this (you don't need to
actually respond to the incoming UDP packets, you want to periodically send
out your own) and never got any good explaination from Symbolics as to why I
couldn't send out UDP packets. 

The basic problem was that when I set up a UDP service to send out a packet to
each UNIX machine, the service immediately got stuck trying to read a packet
(right after the connect packet) from UNIX. UNIX, thinking all this UDP stuff
means you can read packets but you don't have to respond (and they are right),
doesn't respond to RWHO connections, it just wants the RWHO packet. I never
even got as far as sending an RWHO packet, just got stuck on UDP-IN, and noone
ever told me why (too crufty for me to figure out myself).

Anyway, you can have the code if you want, it even decodes the rwho packets it
gets, though I never got as far as pretty-printing them.

Brad Miller
------
miller@cs.rochester.edu {...[allegra|seismo]!rochester!miller}
Brad Miller
University of Rochester Computer Science Department