Commands

PI 102: Introduction to Command Line

FUBAR Labs

Topics

• Basic UNIX Commands
• UNIX Shell Environment and Commands
• [Update and Upgrade Your System]
• [Software Installation ]
• [Command Line Remote Access]
• [System Commands ]
• [Network Commands ]
• [File Directory Commands ]
• [Reboot and Shutdown ]

Basic UNIX Commands

Update and Upgrade Your System

apt-get update Update Packages from a Repository
apt-get upgrade Upgrades Packages Already Installed with Newer Version

apt-get update && sudo apt-get upgrade

Software Installation/Uninstall (Packages, Repositories, Dependencies)

apt-get install package_name Install software/package from a repository

apt-cache search search_string Find package in a repository

apt-get remove package_name Uninstall package

dpkg --list List installed packages

dpkg --status package_name Display information about an installed package

Finding and Sorting things

grep -r "username" . Find a word used in files from the current directory down

ls | sort List all current directory files and sort in numeric alpha order

find . -name "robots.txt" Find a file and print it’s name

Breaking down the command line

. the current directory .. the directory above / the root of the file system && combine two commands \ let one command take several lines | pipe output of one command into the next

      send to a file and erase contents

     send to a file and append contents

What’s in a file?

cat filename

How much space is left?

df -h

What is /dev?

What is /etc?

System Permissions

Permission Type

r           read
w           write
x           execute

Permission Categories

u           user
g           group
o           other
a           all

File Permissions

Change file permissions

chmod                   change mode command
+ - =                       add, subtract or set permissions

Change file ownership
chown    [owner][:[group]] file change the owner and group owner of file or directory

Create your own command alias

How to use tar

tar mode[options] pathname      
tar modes
c       Create an archive from a list of files and/or directories
x       Extract an archive
r       Append specified pathnames to the end of an archive
t       List the contents of an archive

htop vs top

How to kill a process

tmux for multiple consoles

Use screen to talk to a serial port

Change your password with passwd

Interact with your network device

ifconfig

What’s your machines kernel version and details?

uname -a

What command am I really using?

which ls

less is more

man less    manual page for less
cat     display the contents of a file
more        page through the contents of a file
less        scroll up and down and search a file

What’s at the end of a file? Monitor new entries in a file.

tail system.log
tail -f system.log

Terrible superpowers don’t do this:
sudo su -l 
sudo su -l yourfriendsaccount

Getting stuff from the internet with curl or wget