see_shell.sh

#!/bin/bash

# math
echo $(( 1 + 1 ))

# look for a process by port number
lsof -i:3000

# look for a process and print its pid
ps aux | grep ruby | awk '{print $2}'

# look for a port to kill
kill -9 `lsof -t -i:3000`

# update a file using ruby
cat file.csv | ruby -e 'puts STDIN.read.split("\n").join(";")' > new_file.csv

# search directory for files containing a string
grep -rnw . -e search_string

# use a command from history
history | grep ssh
# 396  rm -rf .atom/
# 397  cd ~
# 398  cd Desktop/
!396

# create a screen
screen -S <name>
# ctrl-a then c to make a new tab 
# ctrl-a then [0-9] to switch between tabs
# ctrl-a then d to detach from a screen

# list screens
screen -ls
# There are screens on:
# 	7654.reindex_workspaces	(05/16/2016 09:53:40 PM)	(Detached)
# 	2391.pts-0.job01	(05/09/2016 05:43:15 PM)	(Detached)

# re-attatch to screen
screen -r reindex_workspaces

# kill all screen sessions
pkill SCREEN

# send keystrokes via terminal
osascript -e 'tell application "System Events" to keystroke "TROLLFACE" & return'
# press F8 (key code 100)
osascript -e 'tell application "System Events" to key code {100}'

# loops
while [ true ]; do
# do stuff
done

ids=("1" "2" "3" "4" "5")
for i in ${ids[@]}
do
  echo $i
done