Why bother?

Why do you need to learn the command line
anyway? Well, let me tell you a story. Not long ago
we had a problem where I used to work. There was a shared
drive on one of our file servers that kept getting
full. I won't mention that this legacy operating
system did not support user quotas; that's another
story. But the server kept getting full and
stopping people from working. One of the software
engineers in our company spent the better part of a
day writing a C++ program that would look through the
directories of all the users and add up the space they were
using and make a listing of the results. Since I was
forced to use the legacy OS while I was on the job,
I installed a version of
the bash shell that works on it. When I heard
about the problem, I realized I could do all the
work this engineer had done with this single
line:

du -s * | sort -nr > $HOME/space_report.txt

Graphical user interfaces (GUIs) are helpful for
many tasks, but they are not good for all tasks. I
have long felt that most computers today do not
use electricity. They instead seem to be powered by the
"pumping" motion of the mouse! Computers were
supposed to free us from manual labor, but how many
times have you performed some task you felt sure
the computer should be able to do? You ended up
doing the work by tediously working the mouse.
Pointing and clicking, pointing and clicking.

I once heard an author remark that when you are
a child you use a computer by looking at the
pictures. When you grow up, you learn to read and
write. Welcome to Computer Literacy 101. Now let's
get to work.

Contents

1. 
   What is "the shell"?
   
   
   
   
   1. What's an
      xterm, gnome-terminal, konsole,
      etc.?
   2. Starting
      a Terminal
   3. Testing
      the Keyboard
   4. Using the
      Mouse
   
   
2. 
   Navigation
   
   
   
   1. File System
      Organization
   2. pwd
   3. cd
   
   
3. 
   Looking Around
   
   
   
   1. ls
   2. less
   3. file
   
   
4. 
   A Guided Tour
   
   
   
   1. /
   2. /boot
   3. /etc
   4. /bin,
      /usr/bin
   5. /sbin,
      /usr/sbin
   6. /usr
   7. /usr/local
   8. /var
   9. /lib
   10. /home
   11. /root
   12. /tmp
   13. /dev
   14. /proc
   15. /mnt
   
   
5. 
   Manipulating Files
   
   
   
   1. Wildcards
   2. cp
   3. mv
   4. rm
   5. mkdir
   
   
6. 
   I/O Redirection
   
   
   
   1. Standard
      Output
   2. Standard
      Input
   3. Pipes
   4. Filters
   
   
   
7. 
   Permissions
   
   
   
   1. File
      permissions
   2. chmod
   3. Directory
      permissions
   4. Becoming the
      superuser for a short while
   5. Changing
      file ownership
   6. Changing
      group ownership
   
   
   
8. 
   Job Control
   
   
   
   1. A practical
      example
   2. Putting a
      program in the background
   3. Listing
      your processes
   4. Killing a
      process
   5. A
      little more about kill
   
   Bersumber Dari