Write a Bash Script For Everything

22 April, 2014 - 3 min read

Recently I've been writing a ton of Bash Scripts to do the tedious and monotonous tasks that development can sometimes require. For instance there is a weird bug that I encounter when debugging and Android app on a physical device.

The problem seems to be with a program called EasyTetherUSBEthernet, which will interfere with the Android debugger (ADB). The problem is well documented in StackOverflow posts. This simple little bash script will refresh that program, and restart the debugger server.

#!/bin/bash

# Andrew Gable
# March 2014

#echo password needed
echo -e "Password needed for ktext loading. . . \n"

#load ktext
sudo kextload -v /System/Library/Extensions/EasyTetherUSBEthernet.kext

#sleep just in case
sleep 1

echo -e "ktext unloading \n"

#unload ktext
sudo kextunload -v /System/Library/Extensions/EasyTetherUSBEthernet.kext

#sleep just in case
sleep 1

echo -e "killing adb server \n"

#kill server
adb kill-server

#sleep in just case
sleep 1

echo -e "starting adb server \n"

#start the server back up
adb devices

Once I figured out the power and speed of a bash script I started writing them for everything.

Here is a simple script that logs into an instance of Amazon Web Services through SSH in a new tab (Most likely will only run on OSX). If you want to use this script just make sure to change the path to your .pem file and the user@host to your AWS instance.

#!/bin/bash

#Create a new tab & Login to aws using ssh & correct file
osascript -e 'tell application "System Events" to tell process "Terminal" to keystroke "t" using command down' -e 'tell application "Terminal" to do script "ssh -i /LOCATION/TO/FILE.pem user@HOST" in selected tab of the front window'

The last script I will show you is a work in progress that I am continuing to update daily. I run this script at work as soon as I log in. It updates the latest svn directory it is pointed to if I don't have tomcat open, if tomcat is open then I shut it down and do the update. After a svn update I open Chrome to Gmail.

#!/bin/bash

# Andrew Gable
# April 2014

# Script to check svn, and start the day

echo "Goodmorning Andrew!"

read -p "Andrew, is tomcat off? (y/n)" -n 1 -r
echo
if [[ $REPLY =~ ^[Yy]$ ]]
then
    # If reply is yes then do update
    svn update /Users/user1/Documents/sts/eps
else
    # If reply is no then shutoff tomcat, then update
    /Applications/tomcat/bin/shutdown.sh
    svn update /Users/user1/Documents/sts/eps
fi

# Open Gmail 
echo "Opening Gmail. . . "
open -a /Applications/Google\ Chrome.app https://mail.google.com/mail

echo "Have a good day!"

exit 0

You can see the possibilities for scripting are absolutely endless for scripting. All the seconds it saves you doing the boring fixes, logins, and checks are a life saver. So save a some time, and write a bash script.