I am creating a tutorial for visiting high school students.

Using Node-RED I have a Raspberry Pi that runs a script written in python. I am looking to end the python script from node-RED by passing a keyboardInterrupt (CTRL+C) so that the script ends gracefully and the GPIO is cleaned up for the next run.

I can run the script just fine by using the EXEC block in node-RED and passing "sudo python Documents/python/blinker.py" to the terminal. Problem is because I am not working directly in the terminal I cannot just use CTRL+C to exit the while loop. Is there a way to pass CTRL+C to the terminal from node-RED?

I have attached the python code for those interested:

```
import RPi.GPIO as GPIO
import time

pwmPin = 18
ledPin = 23
butPin = 17

dc = 95

GPIO.setmode(GPIO.BCM)
GPIO.setup(ledPin, GPIO.OUT)
GPIO.setup(pwmPin, GPIO.OUT)
pwm = GPIO.PWM(pwmPin, 50)
GPIO.setup(butPin, GPIO.IN, pull_up_down=GPIO.PUD_UP)

GPIO.output(ledPin, GPIO.LOW)
pwm.start(dc)

print("Press CTRL+C to exit")
try:
        while 1:
                if GPIO.input(butPin):
                        pwm.ChangeDutyCycle(dc)
                        GPIO.output(ledPin, GPIO.LOW)
                else:
                        pwm.ChangeDutyCycle(100-dc)
                        GPIO.output(ledPin, GPIO.HIGH)
                        time.sleep(0.075)
                        GPIO.output(ledPin, GPIO.LOW)
                        time.sleep(0.075)
except keyboardInterrupt:
        pwm.stop()
        GPIO.cleanup()

```

I have tried using the kill and killall commands and that terminates the application but the GPIO.cleanup() isn't run then and any outputs that were on will remain on.

I have also tried passing "echo $'\cc' | ./blinker.py" but get a premissions error.

```
/bin/sh: 1: Documents/python/blinker.py: Permission denied echo: write error: Broken pipe

```

Any help is appreciate