Dr. Mark Humphrys

School of Computing. Dublin City University.

Home      Blog      Teaching      Research      Contact

Search:

CA249      CA318      CA425      CA651

w2mind.computing.dcu.ie      w2mind.org


Lab - Intro to UNIX / Linux


  1. openSUSE 11 distribution of Linux (see System Monitor)

  2. This uses GNOME GUI - many different GUIs - what you see here will not be the same on other Linux/UNIX
    • bottom LHS - Start button
    • bottom RHS - show desktop (or Ctrl-Alt-D) (actually toggle raise/lower all windows)
    • Alt-Tab - switch between applications
    • Keyboard shortcuts on different OSes and GUIs

  3. multiple desktops
    • If you go to corner, it flips to other desktop.
    • To turn this off: Control Center - Desktop Effects - Edges

  4. Web browser - Firefox (also on Win)
  5. Email client - Thunderbird (also on Win)
  6. To view Microsoft Office files see OpenOffice

  7. Explore:
    • Computer - Control Center
    • Computer - More Applications
    • Calculator
    • Take Screenshot (PrintScreen pops up an application to save as PNG)

  8. File Browser
    • dirs = directories (folders)
    • View - Show Hidden Files

  9. hidden files (begin with .)
    • .profile - run at login
    • .bashrc - run for every shell instance (e.g. shell script)

  10. Terminal - bash command line - very powerful - similar to all other Linux/UNIX

  11. command history
    • up/down arrows
    • history
    • !n - repeat command n
    • !string - repeat last command that began with string
    • !c - repeat last command that began with character c
    • !! - last command

  12. see files
    • ls
    • ls -a
    • ls -l
    • ls -al
    • echo * (all non-hidden files)
    • echo .* (all hidden files)
    • echo .* * (all files)
    • ls -l * (if dir, will display contents)
    • ls -ld * (if dir, display name not contents)
    • ls -l .* (don't need -a if going to actually name the hidden files)
    • ls -ld .*
    • . (current dir)
    • .. (parent dir)

  13. show environment variables
    • set
    • env
    • env | sort
    • echo HOME - the string "HOME"
    • echo $HOME - the global (environment) variable HOME
    • PATH = list of dirs searched for command when you type a command, separated by colons (:)

  14. multi-user file system
    • HOME = something like:
        /users/mse1/username  
        /users/gdf1/username 
      
    • For historical reasons, my test account is here:
      /users/gdf1/mhtest09
    • cd to go home
    • cd .. to go up one level:
        /users/mse1
        /users/gdf1
      
    • directory permissions
    • rwx-----x
      • rwx - "user" can do read-write-execute
      • --- - "group" cannot access at all
      • --x - "others" can access files if you know the file name (cannot list contents with ls) - http server can serve up file if it is named

  15. simple text editor - gedit
    • right-click on file - open with gedit
    • $ gedit file &
    • launch any windowed app from command-line - use "&" to detach app or else command-line hangs until app exits
    • saves backup files: file~
    • has syntax highlighting
    • touch file - make new file
    • or just run gedit with new filename - if doesn't exist, gedit creates it

  16. other editors
    • Emacs


Feeds      HumphrysFamilyTree.com

Bookmark and Share           On Internet since 1987.