E-Mail

Forward

This document describes some basic information on communicating with others via E-mail.

What is E-mail

E-mail, short for "Electronic Mail" is a means of communicating with people. The person you are sending E-mail to must have an "E-Mail address" somewhere. Typically, an E-Mail address is a combination of a username, and a machine or hostname. Engineering users will have one of three addresses, depending on which system an account resides. In the following examples, we will assume that the username that a person logs on with is jdoe.

An account based on the City Campus of UN-L, will have an E-mail address of the form:

jdoe@engrs.unl.edu

An account based on the East Campus of UN-L, will have an E-mail address of the form:

jdoe@engec.unl.edu

An account based on the UNO Campus will have an E-mail address of the form:

jdoe@enguno.unomaha.edu

If you are unsure of your E-mail address, please send a mail message to the user known as admin asking what your E-mail address is. Note also, that if you are sending a mail message to a user on the same cluster of workstations, the part after the "@" is not required. For example, when sending mail to admin, you need only type in admin, not admin@engrs.unl.edu.

E-mail addresses explained

In the previous section, you should have found out what you E-mail address is. In this section, we'll describe what was learned. We'll assume that the user's E-mail address is jdoe@engrs.unl.edu for these examples.

A username serves as the basis of the E-mail address on the workstations. This is the jdoe part of the example address. This is the username that someone might use to log in with. Since this is going to be unique for every user on the system, it is a good choice to base an E-mail address on.

The second part of the E-mail address is the hostname, or the name of the machine that one's mail is delivered too. In this case, it is the machine called engrs.unl.edu. You may note that this is not technically any workstation, but it is an alias for a workstation made to keep the address simple. The @is simply a convention that has been adopted to separate the username from the hostname.

The Internet and Domain Names

This particular form of the hostname is called the Fully Qualified hostname. What makes it fully qualified is the addition of the .unl.edu at the end. This indicates a machine that is at the University of Nebraska--Lincoln. Likewise, a .unomaha.edu at the end of an address indicates a machine at the University of Nebraska at Omaha. These are two examples of Domain Names. All of the examples and mailing that we can easily do is based on a computer networked named the Internet. Internet ties together Universities, Colleges, Commercial Sites, Military sites, and many other places that have computer networks. These sites can be here on campus, in the state, anywhere in the world.

This makes it possible for you to send mail from the College of Engineering & Technology workstations, to users on the Engineering Alpha (engvms), the Computer Science machine (cse), among others here on campus. You can also send mail to people at the University of Nebraska at Omaha (Domain Name UNOmaha.edu), and the University of Nebraska Medical Center (Domain Name UNMC.edu). Other sites are Dartmouth College in New Hampshire (Dartmouth.edu), MIT in Boston (MIT.EDU), University of Wyoming (uwyo.edu), Boeing (boeing.com), and many, many others. (Note that the case of the hostname and domain name is not supposed to be case sensitive, while the username may well be case sensitive.)

Mail sent to and from users with the same hostname (eg. engrs.unl.edu) does not have to include the hostname when they are sending a message. If no hostname is specified, then it will default to the current hostname. For instance, if a person with E-mail address jdoe@engrs.unl.edu desires to send mail to user admin@engrs.unl.edu, jdoe does not have to use admin@engrs.unl.edu, but simply admin will do.

Conversely, if the users do not have the same hostname, then the hostname must be specified. For instance, if jdoe@engrs.unl.edu desires to send mail to admin@engvms.edu for some reason, the hostname must be specified. If the hostname is not specified, then the mail will either not make it (known as bouncing), or it will be delivered to the wrong person (if there is a user with the same name as a person on the other host).

Likewise, if the address has a different Domain Name, then the domainname must also be specified. If jdoe@engrs.unl.edu wants to send mail to admin@enguno.unomaha.edu, it must be sent exactly as that. Sending to admin will not work, nor will sending to admin@enguno. It must be fully qualified, as admin@enguno.unomaha.edu.

How to find an E-mail address

By far the easiest way to find someone's E-mail address is to ask them. They should know what their E-mail address is, if they have one. Chances are good, that if they have a computer account, that they also have an E-mail address. Very seldom is this not the case. It is almost always of the form "username@full-hostname". The only other popular format for an address (right now at least) is for a full user's name to be used. For instance, Jane.Doe@engrs.unl.edu. Note that this is an example only, and will not work for mail to our workstations.

On campus addresses are usually fairly trivial to ascertain. If you know the account name of the person, and the machine they are on, that is all you need. If the account is on the Engineering VAX, it will be of the form ETIO123A001@engvms (engvms.unl.edu is the fully qualified hostname of the Engineering VAX). If they are in Computer Science, will probably be on cse and of the form jdoe@cse, or cse0@cse. If they are not in Engineering, and they have an E-mail address, it would likely be of the form jdoe@unl.edu or jdoe@unlinfo.

This paragraph will eventually explain where to get help on finding out non-university of Nebraska mailing addresses. It will be filled in as time and resources permit.

Using a mailer

In order to get your E-mail somewhere, you must use a mailing program. The standard Unix mailer is simply called mail. But, we have a somewhat better and simpler mailer called elm. To start elm, simply type elm at any standard prompt.

Interacting with elm

After elm starts, you will notice that it is menu driven. If you have any mail in your mailbox, the subjects of the first few messages will be displayed.

To send a message, one uses the m (for mail a message) command. Simply press the m key at the "Command:" prompt. The system responds asking for an address to send the message to. If you desire to abort the message, simply press return to get back to the "Command:" prompt. To actually start sending a message, type in the address of who you want to send the message to. A good starting point is to send yourself a message, so type in your username here. Then it will ask for a subject. This should be a short description of the contents of the message. Lastly, it will ask for "Copies to:". For now just press the return key, this field is useful for sending a message to more than one person or group.

At this point, you will be sent into an editor. Which editor is dependent on how you are setup. It will most likely be emacs. But, it could be vi, or jove. We will assume emacs here. This will be a very brief walk-through of emacs. For more help on emacs, type "man emacs", or "help emacs" at a system prompt (not from inside of elm).

Emacs will come on the screen (probably in a new window), and you should see "Emacs: ..." at the bottom of the screen. This is sure sign that emacs is indeed your editor. Just start typing, and the text you type will be displayed in the screen. If you make a mistake, simply backspace over it, or use the arrow keys to move to where you need to fix up the text. When you are finally done, press ctrl-X ctrl-C to exit emacs. Note that this means to press and hold down the control key and X at the same time, followed by depressing control and C at the same time. It will then prompt about saving a file, to which you must type y to indicate to save it (otherwise, you will lose your message!).

At this time, you will be back under elm control. It will prompt whether you should (among other things) send the message, or forget it. Press s, or simply return, and the message will be sent. If you don't want to send the message, type \italic{f} for forget it.

A sample sending session is listed below. Note that your input is in bold.

~> elm
...
Command: m

Send the message to: admin


Subject of message: Test Message

Copies to: 


...edit here...
...exit editor when done...

Please choose one of the following options by parenthesized letter: s

 e)dit message, edit h)eaders, s)end it, or f)orget it.
If you sent the message to yourself, you will get the message in a few moments. At this point (when you get your message), you can just press return, and you will be able to read your message. Then, to get rid of the message, press d for delete, and when you quit elm it will ask if you want to delete your messages. To get back to the index of messages (if you have any more), simply type i for index.

Getting help on elm

To get help while inside of elm, simply type a question mark (?). If you know which key you want help on, press that key after the question mark. If you don't know, then type a question mark (?), as the prompt indicates.

To find out about elm command line options or while not in elm, enter the command man elm from any standard prompt. This will indicate options to elm.

Leaving elm

When you are done sending and reading messages, you usually want to quit. The command for this is simply q, for quit. Quitting elm will update the status of all the messages that you have read, prompt you for deleting any messages you marked for deleting, and whether you want to move messages that you've read to a special folder.

Note that there is also an exit command (x). The exit command does not update the status of messages that you've read, deleted, or otherwise manipulated. It is just as if you had not invoked elm in the first place.

After you have exited elm, you should be back at the standard Unix prompt (~>), and ready for more commands.

Other helpful files of interest

Help files that may be of interest: Man pages that may be of interest