Basic Linux Commands

Linux Commands

List Directory (ls)

ls /

Shows all directories, defaults to current level

ls -l /

– Long flag, shows file permissions. File owner, file size and timestamp for last time edited

Manual page

man ls/

Install with:

 apt install coreutils

Print Working directory (pwd)

pwd

– shows current directory

Change Directory (cd)

cd ../home

– go to home directory – relative syntax

cd /home

– go to home directory – absolute syntax

cd ~/

– go back to root

Make New Directory (mkdir)

mkdir dir_name

– makes a directory called “dir_name”

mkdir dir1 dir2 dir3

– makes 3 directories

Remove Directory (rmdir)

rmdir dir_name

– deletes directory

rmdir dir1 dir2 dir3 dir4

– removes list of directories

Make a File (touch)

touch empty_file

– makes a file?

Copy Files (cp)

cp my_cool_file.txt ~/

– this command copies the file to the root folder

Move Files (mv)

mv .apple .banana .broccoli .milk /home/user/Documents/Hidden

– moves multiple files, same name

mv /home/user/source_file /home/user/moved_files/target_file

– moves and renames file

Delete Files (rm)

rm /home/user/duplicates/target_file

– deletes target_file

Flags – Add flags to change Functionality

–help – display help for command
-r – recursive, means every action executed on the parent will be done unto the child

Find Files (grep)

grep -rw /home/user/Downloads -e "vacation"

– searches for files with the word vacation in them

Options and flags (grep)

-r: search recursively
-w: match the whole word
-n: only in line number
-e: match pattern
–include and –exclude: include and exclude files in the search
–include-dir and –exclude-dir: include or exclude directories in the search

Change Permissions (chmod)

sudo chmod u+x secret_folder/

– “u” stands for “user” and “x” stands for “execute”

sudo chmod g+w secret_folder/

– give the group write permissions

sudo chmod g-r secret_folder/

– take away read permissions from the group

sudo chmod o-r secret_folder/

– remove read permissions for everyone

ls -ld secret_folder/

– check permissions

Change Owner – (chown)

sudo chown cook /home/qwiklab/taco

– make cook the owner of the file taco

Installation Example (Atom)

sudo dpkg -i /home/qwiklab/downloads/atom-amd64.deb

– installs local Debian file

sudo apt install -f

installs dependencies for prev

dpkg -s atom   - verify install

Installation Example (7-zip)

sudo apt install p7zip-full

– installs 7-zip, re-run the command to verify

Uninstalling Example (GIMP)

sudo apt remove gimp

dpkg -s gimp

Extracting an Archive

cd /home/qwiklab/downloads

-change into the directory first!

sudo tar -xvf extract_me.tar

– extracting the file

Archiving files

cd ~ – change into root

tar -cvf Planets.tar --absolute-names /home/qwiklab/documents/Earth /home/qwiklab/documents/Mercury /home/qwiklab/documents/Venus

Targets multiple files with absolute paths originating from root

Blocks and Partitions

Blocks – Blocks are a layer of storage devices that allow individual access to each independently. They allow programs to access storage without worrying about whether the underlying hardware device is a hard drive, solid state drive, flash drive, etc.

Partitioning

Lsblk

– view the devices attached to your machine

df -h

– view disks mounted on the system, -h flag displays human readable format

sudo fdisk -l

– list all partitions

sudo fdisk -l /dev/sdb

– start fdisk utility, h = help, n = new part, d = delete, v = verify, w = commit

Formatting

lsblk