NETWORK MAIL in Unix

Posted by admin

May 6, 2008

There are several different ways of sending mail to users on other
systems. First of all, using the uucp and uux commands. Simply edit a text file
containing the message you wish to send, and uucp a copy of it to the remote
system. Then send it to the target user on that system using the uux command:
uux system!rmail [username] < [pathname]
Where system is the name of the system the target user is on, username is the
name of the user you wish to send the mail to, and pathname is the pathname of
the text file you sent to the remote system. This method works by executing the
rmail command (Receive Mail), the syntax of which is “rmail [user]”, and
redirecting its input from the file you sent to the remote. This method will
only work if the remote allows users from your local system to execut the rmail
command.
The second method is for systems which feature the remote shell (rsh)
command. If the remote system can be contacted by your local system via rsh,
type:
rsh system!mail [user]
And once connected, enter your message as normal.
This last method is the method of sending mail over uucp networks. This
method is the one employed by USENET and other large uucp networks, as well as
many smaller and/or private networks. This method uses the simple mail command:
mail system!system!system![and so on to infinity]!system@user
Where:
The list of systems is the routing to the target system, and user is the mail
recipient on the target system.
Unix1 has entries for unix2 and unix3.
Unix2 has entries for unix1 and unix4.
Unix3 has entries for unix1 and unix5.
Unix4 has entries for unix2 and unix5.
Unix5 has entries for unix3 and unix4.
Now to explain the routing. If unix1 wanted to reach unix5, it couldn’t do so
directly, since it has no means of reaching it (no entry for it in its Systems
file). So, it would “forward” the mail through a series of other systems. For
example, to send mail to the user root on unix5, any of these routings could be
used:
unix3!unix5@root
unix2!unix4!unix5@root
Obviously, the first routing would be the shortest and quickest. So, to mail a
message from unix1 to the root user on unix5, you would type:
mail unix3!unix5@root
Then type in your message and press control-D when finished, and the uucp
facilities will deliver your mail.