Linux Commands Cheat Sheet

Linux Command Cheat Sheet

Basic Linux commands

Command Description
ls Lists all files and directories in the present working directory
ls -R Lists files in sub-directories as well
ls -a Lists hidden files as well
ls -al Lists files and directories with detailed information like permissions, size, owner, etc.
cd or cd ~ Navigate to the HOME directory
cd .. Move one level up
cd To change to a particular directory
cd / Move to the root directory
cat > filename Creates a new file
cat filename Displays the file content
cat file1 file2 > file3 Joins two files (file1, file2) and stores the output in a new file (file3)
mv file "new file path" Moves the files to the new location
mv filename new_file_name Renames the file to a new filename
sudo Allows regular users to run programs with the security privileges of the superuser or root
rm filename Deletes a file
man Gives help information on a command
history Gives a list of all past commands typed in the current terminal session
clear Clears the terminal
mkdir directoryname Creates a new directory in the present working directory or an at the specified path
rmdir Deletes a directory
mv Renames a directory
pr -x Divides the file into x columns
pr -h Assigns a header to the file
pr -n Denotes the file with Line Numbers
lp -nc , lpr c Prints “c” copies of the File
 lp-d lp-P
Specifies the name of the printer
apt-get
Command used to install and update packages
mail -s 'subject'
-c 'cc-address'

-b 'bcc-address'
'to-address'
Command to send email
mail -s "Subject"
to-address < Filename
Command to send an email with an attachment

File Permission commands

Command Description
ls -l to show file type and access permission
r read permission
w write permission
x execute permission
-= no permission
Chown user For changing the ownership of a file/directory
Chown user:group filename change the user as well as a group for a file or directory

Environment Variables command

Command Description
echo $VARIABLE To display the value of a variable
env Displays all environment variables
VARIABLE_NAME= variable_value Create a new variable
Unset Remove a variable
export Variable=value To set the value of an environment variable

User management commands of Linux

Command Description
sudo adduser username To add a new user
sudo passwd -l 'username' To change the password of a user
sudo userdel -r 'username' To remove a newly created user
sudo usermod -a -G GROUPNAME USERNAME To add a user to a group
sudo deluser USER GROUPNAME To remove a user from a group
finger Shows information of all the users logged in
finger username Gives information of a particular user

Networking command

Command Description
SSH username@ip-address or hostname login into a remote Linux machine using SSH
Ping hostname="" or ="" To ping and Analyze network and host connections
dir Display files in the current directory of a remote computer
cd "dirname" change directory to “dirname” on a remote computer
put file upload ‘file’ from local to the remote computer
get file Download ‘file’ from remote to local computer
quit Logout

Process command

Command Description
bg To send a process to the background
fg To run a stopped process in the foreground
top Details on all Active Processes
ps Give the status of processes running for a user
ps PID Gives the status of a particular process
pidof Gives the Process ID (PID) of a process
kill PID Kills a process
nice Starts a process with a given priority
renice Changes priority of an already running process
df Gives free hard disk space on your system
free Gives free RAM to your system

VI Editing Commands

Command Description
i Insert at cursor (goes into insert mode)
a Write after the cursor (goes into insert mode)
A Write at the end of the line (goes into insert mode)
ESC Terminate insert mode
u Undo last change
U Undo all changes to the entire line
o Open a new line (goes into insert mode)
dd Delete line
3dd Delete 3 lines
D Delete contents of the line after the cursor
C Delete the contents of a line after the cursor and insert new text. Press the ESC key to end insertion.
dw Delete word
4dw Delete 4 words
cw Change word
x Delete the character at the cursor
r Replace character
R Overwrite characters from cursor onward
s Substitute one character under cursor continue to insert
S Substitute the entire line and begin to insert at the beginning of the line
~ Change case of individual character