#Linux Notes My personal list of notes and shell (bash) commands I've found usefull. All paths below can be either relative or absolute, regardless of the type shown.
By Charles Boyd

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##Basic Shell Commands Display the path of the current working directory
pwd

Change working directory
cd /path/to/directory

Directory listing
ls
OR
ls -la /path/to/directory

• -l = List
• -a = All Files

Make directory
mkdir directoryname

Remove file or directory
rm /path/to/thing
OR
rm -r directory

• -r = Recursive (required if directory has things in it)

Change user (E.g. change to otherperson)
su otherperson

Run as super user
sudo command --option

Change password
passwd

Get infomation on a command (Example: ls)
man ls

Show shell history
history

Exit the shell
exit

##Environment Show one environment variable (This example: $HOME)
echo $HOME

Show all environment variables
env

PATH var save change (Add the following line to the end of ~/.bashrc)
export PATH=$PATH:/path/to/dir/

##Permissions and Ownership Change permissions of a file/directory
chmod [perm] filename
Where [perm] can be several different string types

Change the owner of a file/directory
chown newowner file.txt

• -R = Operate on files and directories recursively.

##DNS IP DNS Lookup
dig google.com

Revere-IP DNS lookup
dig -x 8.8.8.8

##File Display and Console Output Display an entire file
cat filename
OR
cat < filename

Add line numbers to cat output
cat filename | nl

Octal dump
od -cb filename.txt

Output to file and to the screen
command -option | tee log.txt

##GUI and Detaching Open chrome to a URL
google-chrome bing.com

Open GUI Application and detact from terminal
gedit &!
OR
nohup google-chrome "http://charlesboyd.me" </dev/null &>/dev/null &!

##Third-Party Weather
curl wttr.in/city_name

Check PHP syntax
php -l filename.php

##Shell Scripting
Save output to a bash variable (Example command: ls -l)
MYVAR="$(ls -1)"

Print saved bash variable
echo "${MYVAR}"

##Files and directories
Updates access time of file OR create if it does not exist
touch filename.txt

Directory sizes (human readable)
du -h

Watch file updates
tail -f filename.txt

• -f = follow
• -F = follow and retry

Watch directory changes
watch "ls -lrt | tail -10"

Create link (or "shortcut")
ln -s /path/to/target /the/link/name

• -s = soft link

##Logins
Log into mySQL
mysql -u root -p

SSH to host (And forward ports; e.g. Local port 13306 to remote's local port 3306)
ssh [email protected] -L 13306:localhost:3306

Shutdown
sudo shutdown -h now
or
sudo poweroff

##Client/Server
Output HTTP Responce curl example.com

• -d "Payload here" = Send this data in request and change type to POST
• -X PUT = Change type of request (example: change to PUT)

Retrieve and save remote file to working directory wget example.com/filename

##Searches
TODO

##Common Tools
Text editors
nano
or
vi

Package Manager (e.g. install)
apt-get install packagename

##Simple Commands
Display Current Date/Time
date

Display Running Processes
top

Clear the console display
clear

Output a given string
echo "Hello World"

Print the current user's name
whoami

Display network configuration
ifconfig
or ifconfig /all

Display Mail Queue
mailq