“Where’s the any key?”

Athena, named for the Greek goddess of wisdom, is the main computing environment on campus. Although most students now arrive with their own computers, Athena remains a highly visible aspect of MIT student life.

Begun as Project Athena, it was a major, Institute-wide experiment in the use of computer technologies to improve education at MIT. Project Athena pioneered or refined some of the foundations of UNIX and network computing today, including the X Window System, Kerberos security and Zephyr instant messaging. Now the Athena Computing Environment is the largest single, centrally managed installation of heterogeneous, networked workstations in the world. Athena supports 17 public clusters containing over 350 workstations. Athena workstations are also located in classrooms, laboratories, libraries, living groups, and staff areas. Many are privately owned by faculty and students.

Athena offers computing resources to all undergraduates, graduate students, and faculty. Every student has an account on Athena.

Clusters of computers are scattered about campus. There is a combination for the keypress locks, which is the same for all the public clusters — type “tellme combo” at an athena% prompt. (Most Quickstations are not in locked clusters.) The most visible clusters are the large cluster on the fifth floor of the Student Center and the two “Fishbowl” clusters, one in Building 12 near the Building Four Coffee Shop, and the other in Building 56 on the first floor. There are also about a dozen Quickstations around campus, which are useful if you need to be logged in for a short time (less than ten minutes).

NOTE:This is not meant to be an extensive guide to Athena, merely an introduction. For more extensive help, pick up an Athena Pocket Reference or some of the other printed Athena documentation at the CopyTech in the basement of Building 11, and come to some Athena Minicourses (See web.mit.edu/minidev/www/ for the schedule.)

Getting an Account

Find an open computer with a “Welcome to Athena” screen, and press a key. Then click the mouse on the “Register for an Account” option, and follow the instructions. If you have any problems contact OLC in the basement of the Student Center (W20-021B, x3-4435) or Athena User Accounts in N42 (N42-140, x3-1325). Itusually takes a day or two for your account to become active. Incoming students with network access can now open Athena accounts prior to arriving on campus at web.mit.edu/register/

Be sure you like your username, as it’s nearly impossible to change it. Remember that you’re going to be using this email address for the next few years, and you don’t want to be embarrassed telling recruiters or admissions offices what your email address is. There’s also a good chance that if you use Athena a lot, your username will become your nickname, so choose wisely. Ten years ago, almost all MIT students were introduced to the Internet through Athena, but nowadays most are already proficient. Don’t make the mistake of selecting an Athena usename in the same fashion as you might have chosen an AOL screen name. It’s equally important to choose a good password. Passwords can be changed, however, and should be at least once a term, by typing “passwd” at the athena% prompt. Good passwords usually have both uppercase and lowercase letters as well as numerals and nonalphanumeric characters. A guide to choosing a good password can be found at web.mit.edu/answers/accounts/accounts_choose_password.html. Be sure to never tell anyone your password, as they can mess up your files or change your password so that you can’t log in; furthermore, it is expressly forbidden and you may be faced with disciplinary action if you do so. If someone should somehow manage to change your password, or you forget it, go to N42 with a picture ID and Athena User Accounts will get you out of your fix.

Logging in

At an open computer with a “Welcome to Athena” screen, press a key, then type in your username, and then your password. For security reasons, your password won’t be displayed on the screen.

Using Athena

When you log in, you will see a main terminal window with a prompt, athena%, at which you type commands to the computer. There will also be a bar at the bottom of the screen with several icons on it. This is the GNOME bar, which provides a menu to applications and graphical management of windows. People who have only used Apple or Microsoft operating systems will feel right at home. Several programs, such as the Mozilla web browser and the StarOffice office suite, behave very similarly to their Macintosh and Windows counterparts and have very low learning curves. However, Athena has its roots in the UNIX family of operating systems. Many tasks are still best performed in text windows or from the command line. To get another terminal window from the command line, type “xterm &”.

Filesystem and Basic Commands

The UNIX filesystem is structured into a hierarchical directory structure, the same organization that Mac and Windows folders represent. Pathnames are given using the forward slash (/) character, not the backslash (\) or colon (:).

Athena uses the Andrew File System (AFS) to provide file access from any Athena station. Student groups and courses have Athena “lockers” where their files can be stored. Lockers have a quota, 500 megabytes as of August 2003. Your own locker is given the same name as your username. You can get to another locker by typing “attach <lockername>”. This locker will then show up mounted on your current workstation at /mit/<lockername>. “add <lockername>” will attach a locker and add it to your path so that you can quickly run a program located in a locker. You can give selected people access to your files by setting permissions. Type “olc answers” and select the AFS option to learn more about setting permissions.

More About Your Locker

When you first get your Athena account, you will find several files and directories already created in your locker. The purpose of some of the directories is described below:

Public— A world-readable directory where you can place files that you want everyone to be able to access.

Private— For your private files. Note that the contents of your home directory (and by default any directories you create there) can have their filenames listed by anyone but the files themselves cannot be read. Files in the Private directory can not even be listed by anyone besides you.

www— For web publishing. This is the canonical place to set up your home page, which can be accessed by a URL of the form web.mit.edu/<username>/www/ or www.mit.edu/~<username>/

OldFiles— Your backup directory. Your locker will be automatically backed up every night, and the backups made available to you in this directory, which is read-only. If you accidently delete something which existed the previous day, you can copy it back out of OldFiles. Only the previous night’s backup is made available in this way — if you wait another day to look for the file, it will be gone from the backup as well. The size of your OldFiles directory does not count towards your locker quota. See web.mit.edu/answers/unix/unix_oldfiles.html for more information.

In addition to these, your locker contains a number of “dotfiles” (files that begin with a period, e.g. “.cshrc”). The period keeps them from being listed unless you type “ls -a”. These files contain important configuration and customization information. See web.mit.edu/olh/Dotfiles/Dotfiles.html for more information about them.

Files

Files can be accessed through application programs, which often have graphical file browsers similar to their Mac or Windows counterparts. However, both files and programs can be managed from the command line. To run a program, type the name of it at the athena% prompt. To quit the program, in general, type control-c (press the control key and the c key at the same time) in the terminal window you ran the program from. If the program opens up a new shell (or window), and you will want your prompt back, type an ‘&’ after the program name. (This is called running the program in the background.)

[To use the following examples, replace <filename>, <directory name>, etc., with the appropriate filename, directory name, etc. Comprehensive manual pages on a command can be obtained by typing “man <command name>”.]

Directory Commands:

lslists the files and subdirectories in that directory.

ls -aalso lists your “dotfiles” -- files which the computer accesses when you log in.

cd <directory name>changes directories.

mkdir <directory name>creates a directory which you can then put files in.

File Commands:

more <filename>displays text files in an terminal window, one screenful at a time.

delete <filename>gets rid of file (truly gone after three days).

undelete <filename>retrieves a mistakenly deleted file.

mv <old filename> <new filename>moves a file, effectively renaming it. If <new filename> is an existing directory, the file will be moved inside it.

cp <filename> <duplicate filename>creates a copy of the file.

grep <word> <filename>searches for a word in a file.

Email

MIT offers access to mail through two common methods, POP3 (Post Office Protocol) and IMAP (Internet Message Access Protocol). The important difference between them is that POP3 involves downloading the messages to your locker for reading, while IMAP lets you read your mail on the server. Some prefer IMAP as it allows them to access their email from many locations and computers without logging in to Athena — once mail is downloaded using POP3, it is removed from the mail server — others prefer POP3 because the Athena quota is larger than the mail server quota, and Athena offers greater flexibility in managing saved mail. MH (also xmh and exmh which use MH) uses POP3 to access mail, while Evolution, Pine and WebMail use IMAP.

For a long time, MH (Mail Handler) was the only supported mail client on Athena. Many people still prefer to use it instead of graphical or full-screen text mail clients. MH is rather unique in that all its commands are performed from the command line, and offers some interesting advantages as a result. Here is a brief summary of MH commands:

incincorporates your new mail so that you can read it.

Each message is assigned a number, which is displayed at the beginning of the line when it is incorporated. Commands, such as show and rmm, when not followed by a number, will apply to the current message, which is marked with a plus sign ‘+’.

scanlists all the mail messages you have received and their numbers.

show <message #>displays your mail message, similar to more.

nextdisplays the mail message with the next number.

rmm <message #>deletes the mail message.

compallows you to compose an email message to send using the emacs editor. Put the address or Athena username of who you’re sending it to after the To: prompt. Cc: is for carbon copies to other people, with multiple addresses separated by commas. A topic for the letter can be put on the Subject: line. Begin your letter on the line after the “--------”. Don’t erase this line! When finished, save, exit and type ‘send’.

replis similar to comp, this is to send a reply to a specific message back to its sender.

forwwill include a message so that you can send it on to someone else.

For those who prefer a dedicated mail interface, Evolution and Pine are the supported mail clients on Athena. Evolution includes a contact manager and personal planner, and resembles Microsoft Outlook in many ways. It is rather intuitive to use, and comprehensive help is available from the program’s Help menu. Pine is a text-based program but quite easy to learn. More information can be obtained at www.washington.edu/pine/

WebMail(webmail.mit.edu) provides web-based access to your MIT email account, convenient for email access on the road.

Of course, your MIT email account can also be checked from your home computer using a variety of programs.

Spam filtering is implemented at the mail server level using SpamAssassin, but you must configure your email client to work with it. More information on spam filtering, as well as other email functionality such as auto-response and email forwarding, can be found at web.mit.edu/is/topics/email/

Zephyr

Zephyr is Athena’s instant messaging system. Through zephyr, you can send messages to other Athena users who are logged in. You can also participate in discussion groups (zephyr classes and instances), often centered around various living groups and student activities. Zephyr is often used from the command prompt:

zwrite <username> sends a message to another user logged in at the same time.

zlocate <username>tells if a user is logged on and receiving zephyrs.

You can use a text editor to create a file called “.anyone” in your home directory containing usernames of your friends. Then, type “znol” to find out which of these people are logged in and to be notified when anyone on your list logs in or out. A graphical alternative to znol is xzul -- type “add sipb; xzul &” to open it and pop up a list in a separate window.

Messages sent to you will pop up on your screen by default. Clicking anywhere on the message except the title bar will close it. Be careful not to click a zephyr away before you’ve read it, as there is no record of it anywhere. If you click on the border of the zephyr, or the bar above it, you can move it while keeping it on the screen. Holding down the shift key and highlighting text in the zephyr copies the text. Popup zephyrs are quite bearable for people who use zephyr occasionally, but heavy users of zephyr often turn to the Owl zephyr client instead. Macintosh and Windows zephyr clients exist, with MacZephyr being more mature as you might expect. These can be obtained from itinfo.mit.edu/product?name=zephyr

The Inessential Guide to Zephyr, available from SIPB, gives a broader overview of zephyr, but is somewhat technical in nature. Often, the best source of information about zephyr is an experienced upperclassman.

Text Editing and Word Processing

Emacsis a full-screen visual text editor, developed by free software advocate Richard Stallman as a replacement for the vi editor while he was at MIT. It's extremely extensible and customizable so many that you can web-surf, read your email, send zephyrs, or do just about any computing function without ever quitting Emacs. The most important, though, is how to quit and save your document! This is done by hitting control-x followed by control-c, and answering the question at the prompt.

Framemakeris a fancy “What You See Is What You Get” word processor and is easy enough to learn to do basic processing. It does not run on Linux-Athena workstations, however, but the StarOffice application suite is widely used and supported on these machines. Applixware is also available.

LaTeXis a text formatter. It is more flexible and powerful than WYSIWYG text layout software, but is harder to learn. Many people use it to write large documents such as theses, and anything that requires precise control of mathematical formulae.

There is documentation available and minicourses on each of these. When you don’t have time for a lot of options and just want to jot down some text, Pico is a very simple text editor that does not have very many features but is fast to load and easy to use.

Printing

All of the clusters have printers. cview printers will give a list of all the printers and the clusters they’re located in, as well as how many jobs each one is currently processing.

lpr -P<printer name> <filename>will print out a text or PostScript file.

xdpr -P<printer name>will print a window dump. When the cursor changes to a crosshair, click in the window you wish to print out. Clicking in the root (background) window will print out the entire screen.

lpq -P<printer name>can be used to check the status of the printer, including which jobs are ahead of yours, and whether or not the printer is working.

lprm -P<printer name> will cancel the first pending printing request belonging to you. You can cancel specific print jobs with lprm -P<printer name> <job ID>. lprm -P<printer name> <username> will cancel all your jobs.

When you pick your stuff up from the printer, you can easily tell what is yours by the presence of a header page with your name on it. These header pages are designed to be as not wasteful as possible: they have things like graph paper or music staffs on them.

Thesis printers are available in the main CopyTech Center in 11-004 and in the CopyTech Express in the Student Center (W20).

Screensaving

It is generally considered a good idea to screensave your terminal if you want to leave your terminal for a little while. While Athena has a default screensaver to protect the screens, this does not protect your files from random passers-by who might want to mess with your files. So before you go, type “xlock” at the athena% prompt, or select “Lock” from the GNOME menu. This protects your account in that you need to enter your password before you can get to your account. Do not leave your workstation unattended for more than 20 minutes. Not only is it rude to people who may need the computer, but they will actually be able to log you out after 20 minutes.

Help

Help in learning how to use Athena is readily available. Athena is a powerful and fun environment and we encourage you to explore and learn. Typing help at the athena% prompt will open a web browser with the ‘Athena On-Line Help’ page, which has links to many topics and answers to help you. Browsing through can teach you many things. You can call Athena Consulting at x3-4435, stop by their office at N42, or ask them a question over Athena by typing “olc” at the athena% prompt and following the instructions. Answers to frequently asked questions on Athena can be accessed by typing “olc answers” at the athena% prompt, or on the web at web.mit.edu/answers/. SIPB (Student Information Processing Board), located in W20-557, outside the Student Center cluster, is a group of students who help to create and maintain many services on Athena. They can often answer questions about Athena software. During orientation week, IAP, and for about the first half of each term, Information Systems conducts a series of Athena Minicourses which focus on specific topics, such as Getting Started on Athena, and using editors such as Emacs, LaTeX, and Framemaker, as well as many other useful things on Athena. You can find their complete schedule at web.mit.edu/minidev/www/ from your web browser.

Mailing lists

Much information within MIT is shared via mailing lists, from class announcements to social activities. Athena provides tools to allow you to subscribe and unsubscribe from mailing lists, as well as manage mailing lists of your own. The basic command for manipulating mailing lists is blanche. Typing “blanche” by itself gives you a complete list of commands, but the most commonly used are as follows:

blanche <list name> -a <your username>adds yourself to a mailing list.

blanche <list name> -d <your username>removes you from a mailing list.

If you have trouble using blanche, a menu-driven interface to the same features can be accessed with the mailmaint command or by accessing the WebMoira site at web.mit.edu/moira/ with your web browser.

Never email a list asking to be removed!The list members cannot remove you and will just become upset with the unnecessary mail. The blanche command will not immediately stop you from receiving list mail — it takes at least 4 hours for mailing list database updates to propagate. If you are still receiving mail, contact Athena User Accounts or OLC for help. If you wish to contact the administrator of a mailing list, use the address <list name>-request instead of sending mail to the list itself. If someone does mail a list asking to be removed, send them a discreet personal message — don’t cc: it to the whole list, or you’ll be just as bad.

Personal web pages

Your Athena account can be used to host a personal web site that anyone on the internet can access. Your web site is contained in the www directory in your Athena account — anything you put in there can be accessed over the web. You can place HTML and graphics files in there, or even sound and video as long as your disk quota can handle it. Many people find this useful for keeping in touch with friends back home or directing people who want to know more about them such as potential employers. If you create an index.html file in the directory, people will not be able to list the contents of the directory, they will just receive that page. Once you have built your web site, visit web.mit.edu/is/web/reference/create/faq/announce-page.html for information on how to get your web site listed in the MIT online directory and the MIT Community home page list.

Quota

All Athena users have a disk space quota, although it is quite large and most people will not fill it immediately. To check how much quota you have left, type “quota -v“ at the athena% prompt.

Games

One of Athena’s most important purposes is to provide a distraction when we should all be doing more productive things. The best way in which it does this is by providing a variety of computer games to play. Don’t monopolize computers during busy periods by playing games, though!

add games; ls /mit/games/bin will give you a list of games. Most are executables that you just have to type their names to get them to run. Have fun!

Logging out

It’s really important not to forget to logout before you leave. Click on the Logout button in the lower right corner of your screen, and confirm that you wish to leave, or type logout at the athena% prompt, making sure it listens to you before you go.

Residential Computing

All students can have their own computers in their dorm rooms connected to MIT’s residential network (MITnet). The network supports almost any kind of computer and operating system: Macintosh, Unix, even Windows. To be able to connect to MITnet, which includes a direct connection to the Internet, simply go to rcc.mit.edu and fill out the form there. A Residential Computing Consultant (RCC) will then help you get your computer set up, which usually just consists of giving it the correct IP address.

Once you have your own computer connected to the network, you can use its own software to access various Athena features such as printers and your e-mail. The online help and your RCC can help you out with setting this up if you have problems.

You can bring many parts of Athena to your personal computer through programs available at web.mit.edu/software/ for on-campus download:

• Kerberos implements the basic Athena authentication package and is required for most of the other tools.

• BetterTelnet and NiftyTelnet (Macintosh) and HostExplorer and SecureCRT (Windows) allow you to log onto Athena remotely. You do not get the GNOME bar, but you do get an Athena prompt.

• Virex (Mac) and VirusScan (Windows) are officially supported anti-virus software.

• X-Win32 is an X server for Windows. Combined with HostExplorer/SecureCRT, you can run MATLAB or other specialized graphical programs on Athena without leaving your dorm room. Mac OS X users can download a variety of free X servers from other locations — Apple’s version at www.apple.com/macosx/x11/ is one of the most popular.

• KLPR gives you access to Athena printers. Very useful for people without printers of their own, or when the high quality of a laser is preferred to inkjet output.

• MacZephyr and WinZephyr allow you to participate in the zephyr messaging system, and offer a more convenient interface than the text-only mode of receiving zephyrs in your terminal window.

• TSM is a network backup program. Useful for those who don't want to be bothered with backing up onto CD-Rs or DVD-Rs every once in a while. (Files stored in your Athena locker are backed up automatically, but files on your computer are your own concern.) The backup service costs $7.50 a month per computer.

Some notes on etiquette

If you end up using a graphical client to read your e-mail on your personal computer, it is worth keeping a few things in mind, particularly with regard to mailing lists (every MIT student will find themselves on at least a few mailing lists before they know it!). Most people at MIT use plain text mail readers on Athena, so it is considered very bad form to send mail using HTML or ‘Rich Text’, and even worse to send e-mail attachments such as pictures or word processor documents. Unsuspecting people who do this often get savagely “flamed”, so it’s best to avoid it from the outset! If you are using Eudora to read your mail, avoid HTML mail by answering that you want your message to be in plain text when it asks. It is also easy to set the preferences to always use plain text by choosing Options... from the Tools menu, selecting the Styled Text panel and choosing “Send plain text only”. With Microsoft Outlook it is a similar process — in a new message window choose ‘Plain Text’ from the Format menu, or turn plain text mail on permanently by choosing Options... from the Tools menu, clicking the Send tab, and setting Mail Sending Format to “Plain Text”. You should also turn Quoted-Printable encoding off while you are at it, or all your quotation marks and apostrophes etc. will be rendered as gibberish and your message will be more likely to be automatically rejected as junk mail by various automated antispam systems.

If you have a file you want to share with other MIT people, use your Public directory. Move the file into this directory and then direct interested parties there — this helps avoid clogging up people’s mailboxes and Athena quotas. Some people read their mail over slow networks from overseas so you can’t predict when you’ll be causing someone problems by sending an attachment — just give everyone a break and keep the e-mails text only.