Skip to main content

Common Commands

CD​

  • Change directory
cd folder-name
cd ~ #go to root directory
cd path/to/folder
cd ..

PWD​

  • Print working directory
pwd

Touch​

  • Creates a file
touch index.html
touch file{1..100} #created a files named file1..upto..file100

CP​

  • Copy file or folder to other location
cp source.py destination.py  # cp=copy  
cp -r source-dir/  destination-dir/  #copy everything (-r = recursively)

Rm​

  • Remote file or folder
rm file.py  # rm = remove  
rm -r directory  # remove empty folder(s) recursively  
rm -rf directory_with_content # remove directory with contents inside

MV​

  • Move content to another location
mv source.py destination-dir/  
mv /home/usr/  ./   # move everything in /usr/ to here(./)  
mv /home/usr/doc.py /home/zack/docs/  # move file from usr to zack  
mv hello.py hello-world.py # rename a file with move

Shutdown​

shutdown  # shutdown computer after 1 minute  
shutdown -h now # shutdown immediately  
shutdown 20:14 # shutdown at 20:40  
shutdown -c # stop last shutdown request

Cat, Tail and Head​

  • Commands to view file content
cat smallFile.tx  # view content of files  
tail longFile.txt  # prints the last 10 lines  
tail -n 4 longfile.txt # prints only the last four lines
head longFile.txt # print the first 10 lines  
head -n 4 longfile.txt # prints only the first four lines
less longFile.txt  # read long file part by part

Whatis, Whoami, and Passwd​

passwd  # use to change user password  
whoami  # get the logged in user  
whatis python # print one line description of a command

Which​

  • Used to locate the executable file associated with the given command by searching it in the path environment variable.
which python

Piping​

  • Echo a content into a file, usually used to save the output of a program into a file.
echo "hello world" >> log.txt**

Chmod​

  • Change file permission
#check file permission
ls -l filename

chmod 777 filename-or-folder #Assign full(read, write, and execute) permission to everyone

chmod -R 777 /app/http/ #the current user can do anything on http folder

chmod +x hello.py   #Makes hello.py executable

chmod -x filename #Remove the execution permission of any file

Date​

  • Display current date and time
date
#Sun Jul 24 11:01:53 PM EAT 2022

Find Public Ip Address​

curl ifconfig.me  
#ifconfig.me is a website to get public ip address

Ifconfig​

  • Display the IP and Mac Address of the system
ifconfig

History​

  • Print a history list of all commands
history

W​

  • Display currently logged in users in the system
w
#23:07:20 up 1 day, 12:00,  1 user,  load average: 1.16, 1.01, 1.01
#USER     TTY      FROM             LOGIN@   IDLE   JCPU   PCPU WHAT
#zekaryas :1       :1               Sat11   ?xdm?   2:06m  0.00s /usr/libexec/gd