Command Line (Shell) Tutorial

(0) What is it?

    It's a text based interface to your computer.
    Powerful, arcane, and geeky.
    The two most popular versions are Windows (DOS and its cousins)
    and Unix (csh, bash, tcsh, ...).  Many flavors and varieties.   


(1) How do I get there?

  on Windows 2000 (in labs)
      Start Menu (bottom left) -> Programs -> Accessories -> Command Prompt
      It should give you a window that says
         C:\> 
      which is the command prompt.

  on Mac OS 9
      Doesn't have a command prompt. (Oops.)  

  on Mac OS 10    (in labs)   Launch the "Terminal" program, 
      typically in the menu bar or in the Applications - Utilities folder.  
      Once you start it up, you are in a Unix shell similar to
      the one on akbar.


(2) How about across the network?

    You can connect to a command line on nother remote computer on your network
        (like akbar.marlboro.edu) and use that computer instead of yours.

    Typically this is done with SSH (Secure SHell) these days,
    which is a program on your computer with all the others - 
    or you can download it from the net.  (Go to Google, type 
    "SSH Macintosh", for example.)
   
    On Windows 2000 on the campus machines, you can find SSH
    under Start -> Programs -> SSH Secure Shell

    You can also type "ssh username@host" from the command line of your
    computer to get to the command line of another computer.

(3) OK, I'm there - now what?

    You should be able to perform some file and directory operations.

    On windows, some useful commands are
       dir        -   list the files in your current directory
       cd         -   change to another directory  (.. means "up")
                      Directory paths look like this:  "C:\My Documents\Desktop\"
       control-C  -   stop what you're doing and give me back my prompt
       more       -   display a file (types --more-- at the end of each page)
       help       -   get a list of the commands
       help CMD   -   tell me about command CMD


    on unix, the similar command are
       ls         -   list files
       cd         -   change directory  (.. means up )
                      Directory paths look like this:   /etc/passwd
       control-C  -   same as above
       more       -   same as above
       man ls     -   read the manual pages about the "ls" command

(4) So now what?

    The other tools are basically programs
    that you run from either the point-n-click GUI or from this 
    command line.

    For this class, some of the important tools are

    * Text editors    - where you enter the text of your program.
                        These are worth getting used to.

                        On akbar, type "pico", for example, or "xemacs", 
                        or even "vi".

                        If you try xemacs (which is what I use), then
                        hold down "control-h" for help, and type "t" 
                        for the tutorial.

    * sftp            - move files from one computer to another
                        (This was "FTP - file transfer protocol - but now
                         runs under ssh, hence sftp.)

    * compilers       - javac and java, the actual java thingies themselves.

             Once the java SDK (Standard Development Kit) is installed, then
             at either prompt you can type "javac" to compile a program, and
             "java" to run it from the command line - which is why you're reading
             this, eh?