Quick & Dirty Guide to Getting Started in CSE 341

Reflection X

We'll use Reflection X to give you a graphical interface for your Unix session on Attu (attu.cs.washington.edu).

Logging in from the basement labs

If you're going use the labs, everything is set up for you:

Working elsewhere

We recommend you work in the basement labs where we have checked that the right software is already installed and the directions we provide are correct. If you still want to work elsewhere you have a few options:
  1. Install Reflection-X on your computer, using the CSE department instructions. What a Reflection-X session does is connect you to a CSE UNIX server. Everything you type or click is sent to the server, which sends back to your computer what to display. So you're using the department's software installation.
  2. Install the necessary software (emacs and sml (and possibly sml-mode for emacs) at first, DrScheme later, Ruby after that) on your computer. The links on the course web page should help. Make sure you get the right versions.
  3. For those savvy with terminals and ssh, it is possible to run emacs and sml directly in terminals after connecting via ssh to the department, but it is not particularly pleasant.
  4. You can change your desire to avoid the department labs.

Basic Unix commands

To move around through the directory structure in your xterm window, you'll need to know a few basic Unix commands.
attu4% mkdir mydir
-bash-3.2% ls
mail  mydir
-bash-3.2% cd mydir
-bash-3.2% pwd
-bash-3.2% exit
In the above (the things within the quotation marks are commands to type, don't type the quotation marks themselves): These are just the very minimum basics, but you won't need too much more in 341. For more info on UNIX, see your ACM chapter's tutorials, this UNIX tutorial, material from the first week of CSE303, or many other good resources.

Accessing your UNIX home directories from Windows XP

If you're in the basement labs, your O: drive should already be mapped to your Unix home directory. Look under for the O: drive under "My Computer" in the Start Menu. To accesss your files, go to O:\unix\homes\iws\userid, replacing "userid" with your own CSE account username. All the files you saved while working on Attu should be there.

If you're in the labs and your O: drive isn't mapped, open up a Windows Explorer window (by clicking the "My Computer" from the Start Menu) and in the Tools menu item, select "Map Network Drive" and enter O: for drive and \\ntdfs\cs for folder. Click Finish. If you're at a computer that does not use CSE's name servers, for example in Mary Gates Hall or at home, you will need to use the fully qualified name, \\ntdfs.cs.washington.edu\cs.

For more info on this, see the CSE support page that discusses Microsoft DFS, which is what we just used.


Now that you have your xterm open, let's open Emacs.

Type "emacs &" to open emacs in a new window. Note what happens if you don't type the "&"--you can't do anything in your xterm window. The "&" runs your program, in this case, emacs, in the background.

[GNU Emacs: a labeled diagram]

Emacs uses many key combinations involving the Control and Meta keys. Such key combinations are denoted C-x (Control-x (lowercase)) or M-x (Meta-x). On keyboards that don't have Meta, Alt is usually an acceptable substitute. If Alt doesn't work, ESC-x is equivalent to M-x.

A sequence of key presses is written like C-a C-b M-x, which would mean do the three actions in sequence.

The most important keys in Emacs Some other useful keys: Getting help within Emacs: In addition to the help button on the right...


Once set up, it is more convenient to run SML/NJ in Emacs, but you can also run it directly from the terminal command prompt. Just type "sml" at your terminal command prompt. To get out of SML/NJ, type C-d.

To run it from Windows in the labs, you can find SML/NJ (Standard ML of New Jersey) in Programs under the Start Menu.

To load a .sml file into SML, type "use "filename.sml";" while within SML/NJ.

SML/NJ in Emacs

Remember the Emacs modes we were talking about earlier? You can run emacs in SML mode, but you'll have to set up a few things first. If you're using UNIX from the CSE labs: That's it. To check if it works, you need to restart Emacs. Save your file (C-x C-s) and quit Emacs (C-x C-c), and open it up again. Open any file with a .sml extension (type "C-x C-f" and then "test.sml"). If your mode line says "(SML)", you're set!

If you are not in the basement labs, you need to do the following:

  1. Download SML mode and install it yourself in some directory.
  2. Use the above lines in your .emacs file, but change the first line to:
    (setq load-path (cons "YOUR PATH HERE" load-path))

There are multiple ways to run SML/NJ from within Emacs

Save an SML/NJ transcript

You may want to save output of an entire SML/NJ session. Here are a few ways.

Method 1: Saving within Emacs

If you use the method described above for running SML/NJ under Emacs, you can save the *sml* buffer the same way you save any other buffer: switch to the buffer's window and hit C-x C-s. You will be prompted for a filename. You can save as many times as you wish.

Method 2: Copy and paste

In the X Window System, the idiom for "copy and paste" is to select a region, and then click the middle mouse button (the mouse wheel on an MS mouse suffices) at the spot you want to paste the selected region:

[GNU Emacs in sml-mode with a child SML process]

Method 3: Pipes

This method is only suitable if you want to run a single file through SML/NJ and capture the results, without actually interacting manually with SML/NJ. Invoke SML/NJ as follows:

sml < myinputfile.sml > myoutputfile.txt

The < sign means "redirect standard input from this file", and the > sign means "redirect standard output to this file". Pipes are a very important and powerful feature of Unix. Learn to use them!

Method 4: if you are in SML/NJ for Windows

Right-clicking within the window should bring up options for selecting all, copy/pasting, etc.

Finally, there are other resources, including the (older but not necessarily outdated) course help pages as well as the CS Lab and Support pages.
Acknowledgment: These notes have evolved over the last few years, but are largely based on notes written by Keunwoo Lee in 2001. Last updated by Dan Grossman for Winter 2008.