Linux Commands

Contents

• Directory commands

• File commands

• Redirection commands

Directory Commands

pwd command

Print full path of current directory:

> pwd

ls command

List the contents of the working directory:

> ls

List all contents including hidden files:

> ls -a

List detailed information for all files including permissions:

> ls -l

List files in the order they were modified:

> ls -t

Page through the contents of a directory:

> ls | more

mkdir command

Create a directory:

mkdir [directory name]
> mkdir example

cd command

Change to directory:

cd [directory name]
> cd example

Move up a directory:

> cd ..

Move up 2 directories:

> cd ../..

Move up to an adjacent directory:

cd ../[directory name]
> cd ../test

rmdir command

Delete a directory:

rmdir [directory name]
> rmdir example

File Commands

touch command

Create a file:

touch [file name]
> touch example.txt

rm command

Remove file:

rm [filename]
> rm example.txt

Delete a directory and its contents:

rm -r [directory name]
> rm -r example

cp command

Copy file and rename:

cp [src file] [dest file]
> cp filename1.txt filename2.txt 

Copy file(s) into directory:

cp [filename  …] [directory name]
> cp filename.txt dir1

Copy a directory including its contents into a new directory:

cp -R [directory] [new location]
> cp -R dir1 dir2

mv command

Move file to new location:

mv [filename  …] [new location]
> mv filename.txt dir

Rename old filename to new filename:

mv [old filename] [new filename]
> mv filename.txt example.txt

Move a directory to a new location:

mv [directory] [new location]
> mv example dir1 

cat command

Read file contents:

cat [filename]
> cat example.txt

more command

Show file contents one line (on enter) or one page (on space) at a time:

more [filename]
> more example.txt

less command

Navigate forward and backward in a file:

less [filename]
> less example.txt

Redirection Commands

output operator

Redirect standard output to a file and overwrite the contents: 

output > filename
> cat filename1.txt > filename2.txt

append operator

Append standard output to filename:

output >> filename
> cat filename1.txt >> filename2.txt

input operator

Filename on the right is input into command on the left:

command < filename
> sort < filename.txt

pipe operator

The standard output on the left is piped as input into the command on the right: 

output | command
> cat filename.txt | sort	

sort command

Take standard input and sort it:

> cat filename.txt | sort > sorted.txt

uniq command

Filter out adjacent duplicate lines:

> sort filename.txt | uniq > unique.txt

grep command

Search files for lines that match a pattern and return result:

grep [text] [filename]	
> grep apple filename.txt

sed command

Find and replace the first occurrence of a string in a file: 

sed -i 's/[searchString]/[replacementString]/' [filename]
> sed 's/apple/banana/' filename.txt