Directory Shortcuts

~ - Home Directory
. - Current Directory
.. - Enclosing Directory
/ - Root Directory

Change Directory cd

$ cd ~/Dropbox/code
$ cd ..
$ pwd
/Users/rd/Dropbox

List Files ls

$ ls
$ ls -la
$ la
$ ls -tla

Make a Directory mkdir

$ mkdir projects
$ mkdir -v code
$ mkdir -p code/sinatra-app/public code/sinatra-app/views

Creating Files

$ touch notes.md
$ echo "# Using the OS X Command Line" > cli.md

Getting Help --help and man

$ ls --help
ls: illegal option -- -
usage: ls [-ABCFGHLOPRSTUWabcdefghiklmnopqrstuwx1] [file ...]
$ man --help
$ man ls
$ info ls

Moving and Copying mv and cp

$ mv projects old-projects
$ cp app.rb old-projects/
$ cp -R old-projects really-old-projects

Copy with Progress Bar

$ rsync -r --progress /folder/to/copy /destination/folder

Delete Files and Directories rm

$ rm junk.txt
$ rm -rf really-old-projects

Install Homebrew and Cask

These two apps allow you to install almost anything from the command line.

$ ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
$ brew install caskroom/cask/brew-cask
$ brew install wget
$ brew cask install paintbrush
$ brew cask install --appdir="/Applications" vlc
$ brew search wget
$ brew info p7zip

Other Useful Commands

$ echo
$ grep
$ la | grep .txt
$ tar
$ cat
$ head
$ tail
$ brew
$ tree
$ which
$ whoami
$ curl
$ nano
$ say 'Hello'

Make a Script Executable

Add #!/usr/bin/env ruby to top of the file.

$ chmod +x food_trucks.rb
$ ./food_trucks.rb

Environmental Settings and $PATH

  • /usr/local/bin should be first when using homebrew!: export PATH=/usr/local/bin:$PATH
  • Always append to the end of the $PATH
  • Postres.app: export PATH=$PATH:/Applications/Postgres.app/Contents/Versions/9.3/bin
    $ printenv
    $ echo $PATH
    $ brew doctor
    $ nano ~/.zshrc
    $ nano ~/.bashrc
    

Setting the Default Ruby Version

$ which ruby
$ chruby
   ruby-1.9.3-p545
   ruby-2.0.0-p451
   ruby-2.0.0-p594
   ruby-2.1.2
   ruby-2.1.3
 * ruby-2.1.4
   ruby-2.1.5
$ chruby ruby-2.1.5
$ echo "ruby-2.1.5" > ~/.ruby-version
$ ln -s "/Applications/Sublime Text 2.app/Contents/SharedSupport/bin/subl" /usr/bin/subl
$ which atom
/usr/local/bin/atom
$ la /usr/local/bin/atom

Open Editor

$ cd ~/Dropbox/code/launchvotes
$ atom .
$ subl .

Killing a Frozen Process

$ ps aux | grep safari
$ kill 123

Extracting a tar.gz File

$ tar -zxvf plans_to_take_over_the_wolrd.tar.gz
$ tar -xvjf area51_research_documents.tar.gz2

Unpacking a tar file

$ tar -xvf filename.tar

Zipping a Folder

zip -r archive_name.zip folder_to_compress

Viewing the Contents of a tar.gz File

$ tar -tf filename.tar.gz

Searching File Contents

slooooooow

$ grep -rn collection_select ~/Dropbox/code

faster

$ brew install ack
$ ack --bar
$ ack collection_select ~/Dropbox/code

way fast

$ brew install the_silver_searcher
$ ag collection_select ~/Dropbox/code
$ ag --list-file-types
$ ag "HTTP POST" --markdown

Searching File Names

$ find ~ -iname "time.rb"
$ find . -type f -name "test.log"

Find Files Modified between two Dates

$ find . -type f -newermt 2017-06-21 ! -newermt 2017-06-22

source

Clean up logfiles in your home directory

$ find ~ -iname "*.log" -exec rm {} \;

Searching for Large Files

$ find ~ -size +500000 -print

View Disk Info

$ df -H

Copy Your Public Key to the Clipboard

$ cat ~/.ssh/id_rsa.pub | pbcopy

Find Network Devices

brew install nmap
sudo nmap -sP 192.168.1.0/24

Connect via Secure Shell

ssh username@ip_address
ssh pi@10.0.0.151

Copy files over SSH with Secure Copy

scp source destination
scp ~/install.sh user@ip_address:/Users/rd/install.sh
scp user@ip_address:/Users/rd/Downloads/raspbian.img ~

Watch a Remote Log

ssh ubuntu@example.com tail -f /home/ubuntu/shared/logs/production.log

Change your computer’s hostname

sudo scutil --set HostName your-new-hostname

Setting the priority of a running process

Scale is from +10 (very nice) to -10 (not nice)

ps aux | grep chrome
renice -n -5 -p pid

List USB Devices

system_profiler SPUSBDataType

Resize images larger than 1M

find . -type f -size +1M -exec convert {} -resize 50% {} \;

End

say 'Thank you'