GPIO prober script

probe.sh

#!/bin/sh
gpiomin=480
gpiomax=511
echo "Exporting GPIOs"
for i in $(seq $gpiomin $gpiomax); do
	echo "$i" > /sys/class/gpio/export
done
echo "Getting current state!"
for i in $(seq $gpiomin $gpiomax); do
	cat /sys/class/gpio/gpio$i/value > /tmp/gpio$i
done
echo "Watching for change..."
while true; do
	for i in $(seq $gpiomin $gpiomax); do
		laststate="$(cat /tmp/gpio$i)"
		currstate="$(cat /sys/class/gpio/gpio$i/value)"
		if [ "$laststate" -ne "$currstate" ]; then
			echo "GPIO $i CHANGED FROM $laststate TO $currstate!"
			exit 0
		fi
	done
done