Ruixiang Du

Basic Commands of Ubuntu

  1. Switch between GUI and virtual console:

    Console: Ctrl+Alt+F2 ((F1), F2, F3, F4, F5, F6)

    There are six virtual consoles. The console on F1 is used for debug and log output, so is best avoided.

    GUI: Ctrl+Alt+F7

    If GUI crashes, it might be possible to fix the problem in virtual consoles.

  1. Basic file operation
    • Get help:
       command --help
      

      Run a program: type

       ./programname
      
    • ls: list files

    • cp: copy files and folders

    • mv: move file or folder

    • rm: remove files

    • ln: create a link to a file
       ln -s myfile.doc ~/Desktop/
      
    • grep: search through specified file for a word or phrase
       grep -I wireless myfile.txt
      
    • man: view the manual page for specified command

    • nano: simple text editor

    • umount: unmount attached storage device

    • locate: find specified file; relies on a background datebase that is periodically and automatically upated. The database can be manually updated by typing the “sudo updatedb” command.
  2. sudo and gksu

    if you run a graphical application from the command-line it’s necessary to precede it with gksu instead of sudo.

    Temporarily switching to root: sudo su

    Return to ordinary user account: exit or Ctrl+D

  3. List and kill processes

    ps: ps or ps aux grep firefox

    kill: kill + PID

  4. Zip and upzip

    zip a file:

     zip report.zip report.doc
    

    zip a folder:

     zip -r reports.zip reports
    

    upzip a zip:

     upzip archive.zip
    

    list files in zip:

     upzip -l archive.zip
    
  5. Redirection

    ”>”: redirect to file

    ”»”: redirect to the bottom of file

    ls > listing.txt
    ls >> listing.txt
    
  6. Piping

    pass the output of one command to another

     ls|grep report.doc