Unit 4 Module 3 - Linux Bash Commands

Question 1

What command prints the working directory to the screen?

Answer 1

pwd

Question 2

What command displays names of the files and directories in the current working directory?

Answer 2

ls

(LS)

Question 3

What command navigates between directories?

Answer 3

cd

Question 4

What command displays the content of a file?

Reading File Content Command

Answer 4

cat

Question 5

What command displays just the beginning of a file? ( First 10 lines of text files )

Reading File Content Command

Answer 5

head

Question 6

What command displays just the end of a text file? ( First 10 lines )

Reading File Content Command

Answer 6

tail

Question 7

What command returns the content of a file one page at a time?

Reading File Content Command

Answer 7

less

Question 8

What command searches a specified file and returns all lines in the file containing a specified string?

Searching for a certain keyword in a file

Answer 8

grep

grep OS updates.txt

grep is the command.
OS is the arguement we are looking for
updates.txt is the file we are looking into

Searching for a certain keyword in a file

Question 9

What sends the standard output of one command as standard input to another command for further processing?

Answer 9

| (Piping)

Question 10

What command searches for directories and files that meet a specified criteria?

Answer 10

find

find /home/analyst/projects searches for everything starting at the projects directory.

Question 11

What do you call modifying the behavior of a command and commonly begins with a hyphen ( - ) ?

Answer 11

Options

Question 12

What command creats a new directory?

Answer 12

mkdir

Question 13

What command deletes a directory?

Answer 13

rmdir

Question 14

What command creats a new file?

Answer 14

touch

Question 15

What command deletes a file?

Answer 15

rm

Question 16

What command moves a file or a directory to a new location?

Answer 16

mv

Question 17

What command copies a file or directory into a new location?

Answer 17

cp

Question 18

What command displays permissons to files and directories?

Answer 18

ls -l

( LS -L )

Question 19

What command displays permssions to files and directories including hidden files?

Answer 19

ls -la

(LS -LA)

Question 20

What command changes permissions on files and directories?

Answer 20

chmod

stands for change mode

Question 21

What are the commands for the 3 types of users?

User, Group, and Other

Answer 21

User = u
Group = g
Other = o

The + adds permssions and - minus permissions.

chmod g+w, o-r access.txt

Question 22

What does each letter/symbol mean in this equation?

chmod g+w, o-r access.txt

Answer 22

chmod - Change permssions with files/directories
g+w - Group has gained the permssion to write
, - is giving you the ability to do more commands
o-r - Other is lossing the reading permssion

These are changing the permssions of access.txt

Question 23

What is the character for each of the reading permissions?
1) Read
2) Write
3) Execute

Answer 23

1) Read - r
2) Write - w
3) Execute - x

Question 24

What is this reading permssion?

For files, this is the ability to read the file contents; for directories, this is the ability to read all contents in the directory including both files and subdirectories

Answer 24

Read permission

Question 25

What is this reading permission?

For files, this is the ability to make modifications on the file contents; for directories, this is the ability to create new files in the directory

Answer 25

Write permission

Question 26

What is this reading persmisson?

For files, this is the ability to execute the file if it’s a program; for directories, this is the ability to enter the directory and access its files

Answer 26

Execute permission

Question 27

What does the = command mean?

Answer 27

Assigns permissions for the user, group, or other.

Question 28

What command displays information on other commands how they work?

Answer 28

man

(Manual)

Question 29

What command searches the manual page descriptions for a specified string?

Answer 29

**apropos **

Question 30

What command displays a description of a command on a single line?

ex) whatis nano

Answer 30

whatis

This command is useful when you don’t need a detailed d

ex) whatis nano