Using UNIX

Last modified Friday, 23-Dec-2011 14:36:05 UTC.

Command line Computing (the right thing for Computer Scientists)
- You type a command, the computer obeys
- Terminal sessions
  - Once you have logged into a lab machine, avoid the temptation to start clicking at things. Really, that's for wimps. Actually, it's OK for starting applications, but it's not fast enough for real computing.
  - Start a terminal session ... the little window thing. When you start a terminal session you'll be "in" your home directory.
  - Start another terminal session if you want ... you can have lots of them running at the same time.
  - Now you need to learn some UNIX commands ... the best way is too keep asking someone who knows them. Here're a few:
    - passwd - allows you to change your password
    - date - displays the date and time
    - ls - lists the files in your current directory
    - ls -l - lists the files with extra information
    - ls -a - lists all the files, including hidden ones (they start with a .)
    - cat - displays a file's contents
    - less - displays a file's contents one page at a time
    - cp - copies a file
    - mv - renames or moves a file
    - rm - removes files
    - man - manual pages
    - logout (or control-D) logs you out of the terminal session
- Directories
  - You are probably familiar with the tree-of-directories-and-files most operating systems impose on the disk space. Gotta love it. In review ...
    - There's a place on the harddisk where you can store all your files. That's your home directory.
    - You can create subdirectories to organize your files. Windoze users call subdirectories "folders".
  - Terminal session commands for manipulating directories
    - mkdir - make a subdirectory
    - cd - moves you to another directory (N.B., cd .. moves you to the parent directory)
    - rmdir - remove a subdirectory
  - Use the tree to organize your work.
Editing
- vi - edit a file (for gurus)
  - Plain text editor (i.e., will run over network connections)
  - Available on just about any UNIX system
  - About 35% of all serious UNIX hackers still prefer vi (or a derivative)
  - vim is an improved version, and in the lab running vi will run vim.
  - vimtutor will get you going
- gvim - edit a file (for aspiring gurus)
  - A graphical version of vim, which may be a good way to get into vim.
- emacs - edit a file (for gurus with flat noses)
  - About 35% of all serious UNIX hackers use Emacs. Also widespread use on other operating systems
  - emacs has zillions of extensions
  - Doing ^H t nside emacs will get you going
- gedit - edit a file (for non-gurus)
  - Windowing full-featured editor (i.e., will not, in general, run over network connections)
  - Not available everywhere
  - The Help menu will get you going