LINUX

Question 1

pwd

Answer 1

pwd : It prints the current directory

Question 2

cd

Answer 2

cd :it changes directory

Question 3

cd /…

Answer 3

cd /.. : change directory to an absolute path under the computer directory which is the main directory

Question 4

cd ./…

Answer 4

change directory in the current directory

Question 5

ls or l

Answer 5

It lists the contents of the directory in alphabetical order

Question 6

ls -l

Answer 6

lists the contents in the long way aka more details (the user , the groupe, the date , the time, permissions …), ls -r It lists the contents in revrsed alphabetical order

Question 7

ls -r

Answer 7

It lists the contents in revrsed alphabetical order

Question 8

ls -p

Answer 8

lists contents with file types

Question 9

ls -s

Answer 9

it lists contents sorted by directories/files size

Question 10

sudo (Super User DO):

Answer 10

It allows you to make changes to files and perform administrative tasks for the current command

Question 11

sudo !!

Answer 11

It means run the previous command with sudo,

Question 12

sudo su

Answer 12

it takes you to the root user so you can avoid typing sudo for every command if you want to use it for multiple tasks

Question 13

su (Switch User )

Answer 13

It allows you to change the user su …

Question 14

apt-get

Answer 14

It installs a package or a program that already exists or preinstalled in the unbuntu repositories

Question 15

sudo apt-get install vscode :

Answer 15

it installs the vscode application we use sudo because installation need administrative permission

Question 16

apt-cache …

Answer 16

:It allows us to search for the program

Question 17

apt-cache search vscode*

Answer 17

it searchs anything with the word vscode in it

Question 18

apt-cache policy vsscode

Answer 18

it search for the installed program and it gives you its version and repositories

Question 19

dpkg

Answer 19

it installs , builds and removes debian packages

Question 20

dpkg -i chrome-stable.deb

Answer 20

: is used to install the chrome package

Question 21

dpkg -l

Answer 21

: is used to list the installed packages

Question 22

dpkg –contents chrome-stable.deb

Answer 22

it lists contents of a package

Question 23

cat

Answer 23

It is used to list the contents of a file

Question 24

cat > filename

Answer 24

creates a new file

Question 25

cat filename1 filename2>filename3

Answer 25

 joins two files (1 and 2) and stores the output of them in a new file (3)

Question 26

cat filename | tr a-z A-Z >output.txt

Answer 26

to convert a file to upper or lower case use

Question 27

cp

Answer 27

It is used to copy files from the current directory to a different directory.

Question 28

mv

Answer 28

It is used to move files, although it can also be used to rename files.

Question 29

mkdir

Answer 29

it is used to create a new directory

Question 30

rmdir

Answer 30

it is used to remove a directory

Question 31

rm

Answer 31

it is used to remove directories and the contents with them , "to only remove the directory use rmdir … or rm -r …"

Question 32

touch

Answer 32

it is used to create a blank new file

Question 33

locate

Answer 33

t is used to to locate a file, just like the search command in Windows. "What’s more, using the -i argument along with this command will make it case-insensitive"

Question 34

find

Answer 34

Similar to the locate command, using find also searches for files and directories. The difference is, you use the find command to locate files within a given directory.

Question 35

grep

Answer 35

It lets you search through all the text in a given file. "To illustrate, grep blue notepad.txt will search for the word blue in the notepad file. Lines that contain the searched word will be displayed fully."

Question 36

df

Answer 36

It is used to get a report on the system’s disk space usage, shown in percentage and KBs. "If you want to see the report in megabytes, type df -m."

Question 37

du

Answer 37

:Disk Usage) It is used to check how much space a file or a directory . However, the disk usage summary will show disk block numbers instead of the usual size format. If you want to see it in bytes, kilobytes, and megabytes, add the -h argument to the command line.