Working with Linux files

Question 1

Briefly explain Linux file philosophy

Answer 1

In Linux everything is a file, if it is not a file then it is a process.

Question 2

Explain three basic file types in Linux

Answer 2

1. Ordinary files
   Contains data, text or program instructions
2. Directories
   Store both ordinary and special files
3. Special files
   Provide access to hardware such as disk drives
   Enables you to access a single file using different file names.

Question 3

Color that represent directory

Answer 3

Blue

Question 4

Color that represent compressed archives files

Answer 4

Red

Question 5

Color that represent text files

Answer 5

White

Question 6

Color that represent images

Answer 6

Pink

Question 7

Color that represent links

Answer 7

Cyan

Question 8

Color that represent devices

Answer 8

Yellow

Question 9

Color that represent executables

Answer 9

Green

Question 10

Color that represent broken links

Answer 10

Flashing red

Question 11

What is the important of using colors to represent file types?

Answer 11

It allows the user to see the file type without using any options to ls

Question 12

The standard scheme for file type colors

Answer 12

/etc/DIR_COLORS:

Question 13

What command do we use to find out more about data we are dealing with

Answer 13

file command

i. e #file Tama.txt

Question 14

ls -l First column

Answer 14

represents file type and permission given on a file

Question 15

ls -l Second column

Answer 15

Represents number of memory blocks taken by the file or dir

Question 16

ls -l Third column

Answer 16

Represents owner of the file. The one who created it

Question 17

ls -l Fourth column

Answer 17

Represents group of the owner

Question 18

ls -l Fifth column

Answer 18

Represents file size in bytes

Question 19

ls -l Sixth column

Answer 19

Represents date and time when the file was created or modified last time.

Question 20

ls -l Seventh column

Answer 20

Represents file or directory name

Question 21

Identify these character as they are used to indicate file type in ls -l list: - b c d l p s

Answer 21

• : Regular file eg ASCII txt file, bins, exe or hard links
  b: Block special file. Block input/output device file eg physical hdd
  c : Character special file. Raw input/output device file eg physical hdd
  d : Directory containing other files
  l : Symbolic link file. Links on regular file
  p : Named pipe. Mechanism for IPC
  s : Socket used for IPC
  . : Invisible file

Question 22

How do list invisible files in Linux?

Answer 22

By including -a option to ls command

Question 23

What are the three Linux commands that allows you to view the contents of a file?

Answer 23

1. cat
2. More
3. less

Question 24

How do you display contents of a file with line numbers?

Answer 24

By adding -b option to cat, more or less

Question 25

How do you know which shell you are using (2 ways)

Answer 25

Either check the line for your account in /etc/passwd or type the command: echo $SHELL

Question 26

How do view known shells in Linux system?

Answer 26

cat /etc/shells

Question 27

How do count total number of lines, words and characters in a file?

Answer 27

wc

Question 28

Apart from creating a new file, what are some effects of touch command to a file or directory?

Answer 28

It is used to update the access date or modification date of a file or a directory.

Question 29

How do you make a copy of an existing file?

Answer 29

cp

Question 30

How do you rename a file?

Answer 30

mv

Question 31

How do you delete a file?

Answer 31

rm | rm (for multiple files)

Question 32

Define Directory Tree?

Answer 32

It is a hierarchical structure for organizing files and directories

Question 33

How do you go back in your home directory or other users?

Answer 33

cd ~ or cd~

Question 34

How do you go back one level (last dir)?

Answer 34

cd -

Question 35

How do you see if your home dir has quota system set?

Answer 35

quota -v

Question 36

Explain two ways of displaying path names

Answer 36

1. Absolute A path name is absolute if it is described in relation to root, so it begin with / always 2. Relative Relative path names never begin with /

Question 37

How do you determine where you are within the file system at anytime?

Answer 37

pwd

Question 38

How do you list files in a dir?

Answer 38

ls | ls -l /usr/local (for long list)

Question 39

How do you delete a directory?

Answer 39

rm

Question 40

How do you define an environmental variables in Linux?

Answer 40

Are variables that are defined for the current shell and are inherited by any child shells or processes. Environmental variables are used to pass information into processes that are spawned from the shell

Question 41

What are shell variables?

Answer 41

Are variables that are contained exclusively within the shell in which they were set or defined The are often used to keep track of ephemeral data, like the CWD

Question 42

What does printenv command do?

Answer 42

Print all or part of the environment

Question 43

What does env command do?

Answer 43

Print all exported environment or run a program in a modified environment

Question 44

What does set command do?

Answer 44

Print the name and value of each shell variable

Question 45

Briefly describe commonly used variables in Linux

Answer 45

1. BASH_VERSION - Holds the version of this instant bash - echo $BASH_VERSION 2. HOSTNAME - The name of your computer - $echo HOSTNAME 3. HOME - The home directory of current user - $echo $HOME 4. PATH - The search path for commands - $PATH 5. PS1 - Your prompt settings - $echo PS1 6. TERM - Your login terminal type - echo $TERM 7. SHELL - Set path to login shell - echo $SHELL