The lab itself consists of a number of tasks which will help familiarize you with the computers we will be using in this course. All of the computers in the lab are Linux workstations with XWindows-based user interfaces.
Although we assume in the following that you have never logged into a Linux-based computer, the machines have 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!
One important remark: In our introductory course, MCS177, we encourage students to take advantage of the easy-to-learn user interfaces on the Linux workstations. Our tack in this course is quite different: your work will primarily be done through a Unix shell (also called a terminal), which is a program that allows you to issue system commands; and through emacs, which is a programming and editing environment especially well suited for our needs. In fact, we even encourage you to call up Netscape through the shell, although you are welcome to use any of the many GUI ways of calling it up, should you prefer.
There is a printer in the small room adjoining the classroom/lab. Its name is mcslab, 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.
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). 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.
Check-offs are worth one point each, and will be indicated in bold face in the labs.
We do not include instructions for these task because we figure that most of you already know how to do this. Furthermore, you can't even be reading this unless you are using a web browser such as Netscape, so these are basic boot-up tasks. We will briefly describe how to do this in the first class, and will help anyone who needs help during the first lab.
Our personal homepages are located at
http://www.gustavus.edu/~steveb http://www.gustavus.edu/~karlThe course home page is located at
http://www.gustavus.edu/~mc38/2003J/You may wish to bookmark these ask well.
The Linux computers on campus 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 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.
For this course, we recommend you learn how to navigate the directory structure using a shell or terminal window, which is less system dependent and graphically based than other methods. Following are some tasks which will help you learn how to view and manipulate the directory structure using a Unix shell on a Linux workstation.
A shell (also known as terminal) is a program that allows you to issue commands to the computer's operating system. Unfortunately, these commands are often somewhat arcane and difficult to remember. Fortunately, there aren't many commands that you need to remember.
The easiest way to launch a shell is through the main menu for the Linux workstation. On a Linux workstation, get the main menu by holding down the left mouse button on the "K" in the lower left corner of the screen and select the "Application" submenu and the "xterm" submenu item.
The shell window will pop up, and you will be presented with a command line prompt from which you can issue commands. How it looks will vary from person to person, but will probably end with the % or > character.
As described before, each computer user at Gustavus has a home directory that is stored on the central file server. When you start up a shell, the present work directory is your home directory. To see what that is, type pwd. (You must press the "Enter" key to actually issue the command.) Do so. Your home directory should end with your username.
You can view the present work directory by entering the command ls. This will list all files and directories in the present work directory.
To get a more informative listing, type ls -l. This gives more information about the files and directories.
To add a directory called mcs273 into your home directory, type mkdir mcs273. Do so, and then type ls -l to see the newly created sub-directory.
pwdto show that you are there and a directory listing to show that it is currently empty.
You can move to mcs273 by typing cd mcs273 (think of cd as Change Directory). Do so.
cd .. will cause you to move up one directory
in the file system; typing
cd will take you to your home
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!