This is a little program for pulsing a GPIO on a raspberry pi to trigger a door relay. If it is not passed an argument, it opens the first relay. If it is passed an integer argument (1-6), it opens the corresponding relay.
This requires the wiringpi plugin. This can be retrieved from https://github.com/WiringPi/WiringPi
Wiring is as follows: GPIO pin -> Level Shifter -> Relay repeat for each of the (up to 6) door relays