NAME

systemd-gpio - run commands when a button on a GPIO pin is pressed

DESCRIPTION

Use systemd to configure commands to run when a button attached to a GPIO pin is pressed, released, or held.

To configure a GPIO pin, create a file called /etc/gpio/N, where N is an integer pin number following the gpiozero pin numbering convention. Once you have populated the configuration file, activate the button by running the following command, replacing N with the pin number:

sudo systemctl enable --now gpio@N.service

ENVIRONMENT

Button behavior. See the documentation for the corresponding constructor arguments of gpiozero.Button.

Commands to run when the button is held, pressed, or released, respectively. See the documentation for the corresponding properties of gpiozero.Button.

FILES

/etc/gpio/N

Configuration file for GPIO pin N, where N corresponds to the gpiozero pin numbering. The file should be in the systemd EnvironmentFile syntax and may define any of the environment variables listed above.

HISTORY

This project is inspired by https://github.com/ali1234/systemd-gpio. The main difference is that we are using gpiozero rather than WiringPi, because WiringPi is no longer maintained.

EXAMPLES

The following example configures GPIO 23 so that when it is pressed, it prints a message to all TTYs, and when held, shuts down the machine:

# /etc/gpio/23
GPIO_HOLD_TIME=5
GPIO_WHEN_PRESSED="wall 'Hold the power button for 5 seconds to power off.'"
GPIO_WHEN_HELD=poweroff

To activate the pin, run the following command:

sudo systemctl enable --now gpio@23.service

SEE ALSO

systemctl(1), systemd.exec(5)