Unix/Linux Command Line Reference

Moving around in the file system

Examining Files

pwd

Print Working Directory show what directory youre in

file

Determine the type of a file

ls

List the contents of a directory

cat

Concatenate a file

ls la

List the contents of a dir including hidden files

less

View text files and paginate them if needed

cd

Change to your home directory

Manipulating files and directories

cd /path/

Change directory to /path/

cp file1 file2

Copy filename1 to filename2

cd ..

Change directory up one path

cp r dir1 dir2

Copy directory1 to directory2

Job management

mv file1 file2

Move or rename file1 to file2

ps

Display your current active processes

rm file

Remove file1

jobs

Show all jobs you have executing

rm r dir1

Remove directory1

kill -9 pid

Terminate the process owned by PID (process identifier)

rm rf dir1

Remove directory1 (does not need to be empty

killall proc

Terminate all processes named proc

rmdir dir1

Remove an empty directory

bg

lists stopped or background jobs; resume a stopped job in the background

mkdir dir1

Make directory1

fg

Brings the most recent job to foreground

touch file1

Create an empty file named file1

Shortcuts

head file1

Show the first 10 lines of a file

Ctrl+C

Halts the current command

tail file1

List the last 10 lines of a file

Ctrl+Z

Stops the current command, resume with fg in foreground or bg in background

Searching

 

Ctrl+W

Erases one word on the current line

grep pattern files

Search for pattern in files

Ctrl+U

Erases the whole line

grep -r pattern dir

Search recusively for pattern in dir

Ctrl+R

Type to bring up a recent command

command | grep pattern

Search for pattern in the output of command

!!

Repeats the last command

locate file

Find all instances of file

exit

Log out of current session

File Permissions

System Info

chmod octal file

Change the permissions of file to octal, which can be found separately for user, group, and world by adding: 4 (read), 2 (write), 1(execute)

date

Show the current date and time

cal

Shows this month's calendar

EX:chmod 777

read, write, execute for all

man command

Show the manual for command

EX:chmod 755

RWX for owner, RX for group and world

Dont forget about TAB completion from the command line!