# Variables
GPIONUMBER=27
COUNT=0

# Command to grep ps for 'node'. If found, returns 0, else returns 1.
ps ax | grep node | grep -q -v grep ; echo $?

echo "0" > /sys/class/gpio/gpio${GPIONUMBER}/value

If [ $? -gt 0 ]
then
                sleep 5
                echo "1" > /sys/class/gpio/gpio${GPIONUMBER}/value
else
        until [ $COUNT -gt 100 ]; do
                echo "1" > /sys/class/gpio/gpip${GPIONUMBER}/value
                sleep 0.05
                echo "0" > /sys/class/gpio/gpio${GPIONUMBER}/value
                sleep 0.05
                let COUNT=COUNT+1
fi