Linux Commands Cheat Sheet

By: Author David Cao

Posted on Last updated: July 14, 2023

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Categories Linux

In this Linux command line cheat sheet, we will learn:

Basic Linux Commands
File management user management Linux Commands
Programing Linux Commands
Job management Filesystem management Linux commands
Process management Linux Commands
Shortcuts
network
System Info
Searching
File Permission

Table of Contents

Basic Linux Commands

cat – Joins and displays files
cp – Copies files
cpio – Creates an archive, restores files from an archive, or copies a directory hierarchy
cut – Selects characters or fields from input lines
diff – Displays the differences between two text files
emacs Editor
expand – Converts TABs to SPACEs
find – Finds files based on criteria
grep – searches for a pattern in files
gzip – Compresses or decompresses files
head – Displays the beginning of a file
join – Joins lines from two files based on a common field
less – Displays text files, one screen at a time
ln – Makes a link to a file
ls – Displays information about one or more files
man – Displays documentation for utilities
mkdir – Creates a directory
mv – Renames or moves a file
nl – Numbers lines from a file
od – Dumps the contents of a file
paste – Joins corresponding lines from files
rm – Removes a file (deletes a link)
sed – Edits a file noninteractively
sort – Sorts and/or merges files
split – Divides a file into sections
tail – Displays the last part (tail) of a file
tar – Stores or retrieves files to/from an archive file
touch – Creates a file or changes a file’s access and/or modification time
uniq – Displays unique lines from a file
vim Editor
wc – Displays the number of lines, words, and bytes in one or more files

File management user management Linx Commands

cd – Changes to another working directory
chgrp – Changes the group associated with a file
chmod – Changes the access mode (permissions) of a file
chown – Changes the owner of a file and/or the group the file is associated with
date – Displays or sets the system time and date
df – Displays disk space usage
dmesg – Displays kernel messages
du – Displays information on disk usage by directory hierarchy and/or file
finger – Displays information about users
kill – Terminates a process by PID
killall – Terminates a process by name
nice – Changes the priority of a command
nohup – Runs a command that keeps running after you log out
ps – Displays process status
renice – Changes the priority of a process
sleep – Creates a process that sleeps for a specified interval
stat – Displays information about files
stty – Displays or sets terminal parameters
sysctl – Displays and alters kernel variables at runtime
top Dynamically displays process status
umask Specifies the file-creation permissions mask
w Displays information about local system users
which Shows where in PATH a utility is located
who Displays information about logged-in users

Programing Linux Commands

configure – Configures source code automatically
gawk – Searches for and processes patterns in a file
gcc – Compiles C and C++ programs
make – Keeps a set of programs current
mawk – Searches for and processes patterns in a file
perl – Scripting language
python – Programming language

Job management Filesystem management Linux commands

at – Executes commands at a specified time
cal – Displays a calendar
crontab – Maintains crontab files
echo – Displays a message
expr – Evaluates an expression
fsck – Checks and repairs a filesystem
mkfs – Creates a filesystem on a device
screen – Manages several textual windows
tee – Copies standard input to standard output and one or more files
test – Evaluates an expression
tr – Replaces specified characters
tty – Displays the terminal pathname

Process management Linux Commands

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 on your system

Shortcuts

Ctrl+C – halts the current command
Ctrl+Z – stops the current command, resume with
fg in the foreground or bg in the background
Ctrl+D – log out of current session, similar to exit
Ctrl+W – erases one word in the current line
Ctrl+U – erases the whole line
Ctrl+R – type to bring up a recent command
!! – repeats the last command
exit – log out of current session

Network

ping host – ping host and output results
whois domain – get whois information for domain
dig domain – get DNS information for domain
dig -x host – reverse lookup host
wget file – download file
wget -c file – continue a stopped download

./ – curret directory right now
../ – previous directory
~ – the users home directory
| – pipe the output of one command into another
> – use command on the following file (overwrite)
>> – use command on following file (appends)

Compression

tar cf file.tar files – create a tar named file.tar containing files
tar xf file.tar – extract the files from file.tar
tar czf file.tar.gz files – create a tar with Gzip compression
tar xzf file.tar.gz – extract a tar using Gzip
tar cjf file.tar.bz2 – create a tar with Bzip2 compression
tar xjf file.tar.bz2 – extract a tar using Bzip2
gzip file – compresses file and renames it to file.gz
gzip -d file.gz – decompresses file.gz back to file

System Info

date – show the current date and time
cal – show this month’s calendar
uptime – show current uptime
w – display who is online
whoami – who you are logged in as
finger user – display information about user
uname -a – show kernel information
cat /proc/cpuinfo – cpu information
cat /proc/meminfo – memory information
man command – show the manual for command
df – show disk usage
du – show directory space usage
free – show memory and swap usage
whereis app – show possible locations of app
which app – show which app will be run by default

Searching

grep pattern files – search for pattern in files
grep -r pattern dir – search recursively for pattern in dir
command | grep pattern – search for pattern in the output of command
locate file – find all instances of file
find /dir/ -name name* Find files starting with name in dir
find /dir/ -user name Find files owned by name in dir
find /dir/ -mmin num Find files modifed less than num minutes ago in dir

File Permissions

chmod octal file – change the permissions of file to octal, which can be found separately for user, group, and world by adding
4 – read (r)
2 – write (w)
1 – execute (x)

IO Redirection

cmd < file Input of cmd from file
cmd1 <(c
md2) Output of cmd2 as file input to cmd1
cmd > file Standard output (stdout) of cmd to file
cmd > /dev/null Discard stdout of cmd
cmd >> file Append stdout to file
cmd 2> file Error output (stderr) of cmd to file
cmd 1>&2 stdout to same place as stderr
cmd 2>&1 stderr to same place as stdout
cmd &> file Every output of cmd to file

Linux Troubleshooting Guide:

Linux Learning Guide: