A script to start a random Application in OS X

runrandom.sh

#!/bin/bash

##
# RunRandom
# - A script to run n random applications.
#
# Copyright 2011 Luke Channings
#
# Usage:
# To run a single app: ./runrandom.sh 
# To run 10 random apps: ./runrandom.sh 10
##

# Declare app index.
i=0

echo "Building a list of applications."

# Loop through applications.
while read -r location; do
	# Add the application to the array.
	app[$i]=$location
	# Increment the loop.
	(( i += 1 ))
done < <(find /Applications -name *.app 2> /dev/null)

echo "$i Applications found."

# Declare random index.
x=0

# Establish how many applications to run.
if ([ ! -z "$1" ] && [ $1 -eq $1 ]) 2> /dev/null; then
	n=$1
elif [ -z "$1" ]; then
	n=1
else
	echo "NaN."
	exit 
fi

echo "Running $n random application(s)."

# App Execution loop.
while [ $x -lt $n ]; do
	# Fetch a random number.
	R=$RANDOM
	N=`expr $(echo $R | wc -c) - 1`
	d=`awk "BEGIN{print 10^$N}"` # Divisor.
	R=`awk "BEGIN{print ($R/$d)*$i}"`
	R=${R/\.*}
	# Make sure the random number isn't too large.
	while [ $R -gt $i ]; do
		# Half the number until it is small enough.
		R=`expr $R / 2`
	done
	# Run a random application.
	open "${app[$R]}"
	# Increment the loop.
	(( x += 1 ))
done