"rsh" question

[Melinda Shore]

In article <1991Apr15.185835.7025 at nrcnet0.nrc.ca> ng at cfd.di.nrc.ca writes:
>When you telnet, normally user id is used. However when rsh or rlogin,
>user number is used.

Nope.  The login name is used by both rsh and rlogin.  Telnet uses
neither (i.e. it's not part of the protocol) - it just provides a 
connection.

>Side question: How come I can never reply by mail to addresses like
>johnk at locus.com or somebody at somehost.awdpa.ibm.com ? They all bounced back
>with host unknown error.

You're probably not running a sendmail that understands mx records.  If
you are (sendmail 5.61 and later), then your sendmail.cf file probably
isn't configured correctly.  If it is correct, then you probably aren't 
using the domain name service.  If you are using dns, then it probably 
isn't set up correctly.  
-- 
                    Software longa, hardware brevis
Melinda Shore - Cornell Information Technologies - shore at theory.tn.cornell.edu