MCS-177 Lab: Getting Started

Introduction

The purpose of this lab is to familiarize you with our computer facilities and with simple programming in Scheme. You will also learn how to use the web browser Netscape (if you don't already know) in order to access course materials. You do not need to hand anything in and you will not be graded on your work (except if you choose to work in part on your first homework).

The lab itself consists of a number of tasks which will help familiarize you with the computers we will be using in this course. In this course we will be using computers running the Linux operating system with the XWindows-based user interface.

Although we assume in the following that you have never logged into this type of computer, is had a reasonably intuitive user interfaces. Therefore, rather than explaining how to do each task in gory detail, we will simply give you the tasks together with some optional explanations you can refer to if you find the tasks obscure or otherwise difficult. However, we encourage you to try to figure out how to do the tasks on your own. When that doesn't work, don't be shy: ask!

Resources

The classroom/lab we will be using for the lab sessions (Olin 326) consists of 16 Linux workstations which are part of the campus-wide computer network.

There is a printer in the small room adjoining the classroom/lab. Its name is mcs-lab, so if you need to select a printer to print to, that is the one you should use when in the third-floor Olin computer labs.

Each Gustavus student has been given a computer account; this handout assumes that you already have read your account letter and changed your password. If not, and you need help with this, let one of us know. It does not matter which workstation you log into; you will have access to all your files on all computers, since they are stored on a central file server.

One important general point about the Linux computers: to type into any window with the keyboard, your mouse must be pointing into that window.

The following instructions assume some familiarity with such terms as single-click, double-click, and drag, which refer to the use of the mouse (the small doohickey next to the keyboard). All these actions should be done with the mouse's left button, unless specified otherwise. If you don't understand something or if the instructions seem impenetrable, don't worry. These are examples of things better shown than described in words. Ask your lab instructor or one of the tutors to explain it to you. Also, feel free to talk with your fellow students. Computers are unfortunately fraught with many arcane terms, and defining them all would unduly clutter these handouts. Fortunately, if you are not shy about asking someone when you have a question, you should get the hang of it fairly quickly.

In lab

  1. Login to a Linux workstation.

    Use your username and password, as given in your account letter, or later changed by you.

  2. Launch Netscape.

    Netscape is a web browser that is supported on all platforms here at Gustavus. Much useful information is available on the web, so you will be well-advised to learn how to use Netscape, if you haven't already done so. In particular, I have constructed a web page for this course.

    You will see a bar accross the bottom of the screen, this is your toolbar. On the left side there is a button with a K on it. (screen image). That is your "K menu", the "start menu" on Windows NT is similar to this. Click on the K to bring up a list of submenus. The Application menu contains most of the applications that you will need for this course. Click on the Applications menu and then on the Netscape item to start netscape. You may need to wait for several seconds until Netscape starts. If this is the first time have used the current version of Netscape on this system, a window will pop up describing the license agreement you must accept in order to use Netscape. After reading through and (presumably) accepting that agreement, the Netscape window will pop up.

  3. Use Netscape to access the Gustavus and the course homepages.

    Locate the Gustavus Adolphus College homepage by entering http://www.gac.edu/ in the Location box and pressing Enter. Since you may not want to remember this address for next time, select ``Add Bookmark'' under the Bookmarks menu. Next time you want to find the Gustavus homepage, select ``Gustavus Adolphus College'' under the Bookmark menu.

    The course homepage is located at

       http://www.gac.edu/~mc27/
    

  4. Become familiar with the directory structure.

    The Unix computers on campus (among which are the Linux workstations) share a tree-structured file system. This means that the files on the computers are located in directories, which may themselves include files and subdirectories, which may contain files and other subdirectories, ....

    When your account was created, you were given a home directory in which you can store and create files and subdirectories. This home directory resides on a file server maintained by the Department of Information Technology (which is located on the first floor of Olin Hall). Since your home directory (as well as other user accounts) are automatically loaded onto the Linux computers, it really doesn't matter which specific computer you use. Whichever computer you use, you will have access to the files you created in your previous sessions.

    Rather than describing in this document how to manipulate the file system on Linux workstations, we have created a separate web pages for each system. You also have the option of using a a shell or terminal window, which is less system dependent and graphically based. Click on the hyper-link below to go to the page that is appropriate for your system:

  5. Start up DrScheme and play around.

    Click on the following link for some tasks that will help you learn how to run Scheme in the DrScheme programming environment:

  6. When you are finished, quit DrScheme and then logout.

    A panel will pop up asking whether you really want to quit. (If you modified the definition window more recently than you saved it, you'll be asked about it as well.) You can then logout.

    To logout move the mouse cursor to an open area of the screen and hold down the right mouse button; the last menu item is to logout

Follow-up

The Linux workstations are general purpose computers that have a wide range of applications, including word processors, electronic mail, mathematical applications (Maple), and programming tools, to name just a few. As long as you remain a responsible user, you are welcome to use these applications as you please for other academic purposes. However, if you are working on something other than a math or computer science project, and all the machines fill up, please give your machine up for a student working on math or computer science. That way, with a little common courtesy, we can get the maximum benefit out of these facilities and still respect the fact that they've been funded for use in mathematics and computer science.

One problem you will encounter is how to make yourself aware of all of the applications available to you. This is a rather daunting task, and one which we will not directly address in this course. Instead, we suggest that you make use of the main source of useful computer arcana and trivia we have found, namely your fellow computer users. We are always learning new things from our students. So don't be shy!