Linux CheatSheet for Developers

File Commands

Command	Description
`pwd`	Show current directory
`mkdir dir`	Make directory called dir
`mkdir -p folder/folder2`	Make a directory folder and another directory folder2 in it
`cd dir`	Change directory to dir
`cd ..`	Go up a directory
`cd`	Change to home directory
`ls`	List contents of directory
`ls -r`	Reverse list contents of directory
`ls -t`	List contents of directory based on time
`ls -al`	Formatted list of contents for the directory including hidden files
`rm file`	Delete file
`rm -r dir`	Delete directory dir
`rm -f file`	Forcibly delete the file
`rm -rf dir`	Forcibly delete the directory dir
`rm -rfv dir`	Forcibly delete the directory dir with verbose output
`cp file1 dir`	Copy file1 to inside of dir
`mv file1 dir`	Move/Cut file1 to inside of dir
`touch file`	Create file
`cat file`	Show the Contents of file
`head file`	Display first 10 lines of files
`tail file`	Display last 10 lines of files
`gpg -c file`	Encrypt a file
`gpg file`	Decrypt a file
`wc`	Show the Number of words,lines,bytes in file

Command	Description
`chmod octal file`	Change the permissions of file to octal for user, group and world by adding: 4 - read( r ), 2 - write( w ), 1- execute ( x )
`chmod 777 file`	Read, write, execute for all
`chmod 755 file`	rwx for owner, rx for group and world.

Command	Description
`sudo command`	Runs command as root. (If a command requires a higher permission you might have to run it with sudo)
`su`	Runs an interactive shell as root

Command	Description
`ssh user@host`	Connect to host as user
`ssh -p port user@host`	Connect to host on port port as user

Command	Description
`date`	Show the system date and time
`cal`	Show this month's calendar
`uptime`	Show system's uptime
`free`	Display amount of free and used memory in the system
`w`	See who is online
`whoami`	See who you are logged in as
`uname -a`	Show kernel information
`man command`	Show the manual for any command (exit with q)

Command	Description
`Ctrl + A`	Moves the cursor to the start of a line
`Ctrl + E`	Moves the cursor to the end of the line
`Ctrl + F`	Move one character forward
`Ctrl + B`	Move one character backward
`Ctrl + L`	Clear the terminal screen
`Ctrl + C`	Halts the current command
`Ctrl + D`	Log out of current session
`Ctrl + W`	Erases one word in current line
`Ctrl + U`	Erases entire line

Command	Description
`nano file`	nano is a small and friendly editor
`vi file`	vi is a powerful text editor where every action is done though the keyboard. How to exit vim/vi (Trust me you'll need to know it)
`vim file`	vim - Vi IMproved is an improved version of the vi editor. Like vi, every action is done through the keyboard.

Command	Description
`tar cf archive.tar directory`	Create tar named archive.tar containing directory
`tar xf archive.tar`	Extract the contents from archive.tar
`tar czf archive.tar.gz directory`	Create a gzip compressed tar file name archive.tar.gz
`tar xzf archive.tar.gz`	Extract a gzip compressed tar file
`tar cjf archive.tar.bz2 directory`	Create a tar file with bzip2 compression
`tar xjf archive.tar.bz2`	Extract a bzip2 compressed tar file

Command	Description
`df -h`	Show free and used space on mounted filesystems
`df -i`	Show free and used inodes on mounted filesystems
`fdisk -l`	Display disks partitions sizes and types
`du -ah`	Display disk usage for all files and directories in human readable format
`du -sh`	Display total disk usage off the current directory

Command	Description
`grep pattern file`	Search for pattern in file
`grep -r pattern directory`	Search recursively for pattern in directory
`locate name`	Find files and directories by name
`find /home/xyz -name 'prefix*'`	Find files in /home/xyz that start with "prefix"
`find /home -size +100M`	Find files larger than 100MB in /home

Command	Description
`ip a`	Display all network interfaces and IP address
`ip addr show dev eth0`	Display eth0 address and details
`ethtool eth0`	Query or control network driver and hardware settings
`ping host`	Send ICMP echo request to host
`whois domain`	Display whois information for domain
`dig domain`	Display DNS information for domain
`dig -x IP_ADDRESS`	Reverse lookup of IP_ADDRESS
`host domain`	Display DNS IP address for domain
`hostname -i`	Display the network address of the host name
`hostname -I`	Display all local IP addresses of the host
`wget http://domain.com/file`	`Download http[]()://domain.com/file`
`netstat -nutlp`	Display listening tcp and udp ports and corresponding programs

Command	Description
`env`	Displays all environment variables
`echo $VARIABLE`	Displays value of variable