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I have a headless Debian ARM machine that I'm running Node on. The device has hard buttons that are mapped to normal keyboard events using gpio-keys.

My goal is to capture the global events from both the hard buttons as well as any attached keyboards in Node. I need a solution that can capture the keydown/keyup events independently of the terminal that it's run in (it will be run over an SSH session). It doesn't have to be cross-platform, as long as it works on ARM Debian I'll accept it.

I am imagining something reading directly from whatever sysfs attributes are necessary, but that's not a requirement.

Can anyone help me on this? I've been stuck for a while.

Wasabi Fan
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1 Answers1

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One of the device files /dev/input/event* will represent the gpio-keys device. You can figure out which one in a number of ways; one easy one is to look at the contents of the uevent file for the device, e.g. /sys/class/input/event0/device/uevent. It'll contain a number of useful key-value properties.

Once you've figured out which device you want, you can open and read from it. It'll return a stream of struct input_events, as defined in <linux/input.h>. These events will correspond to presses and releases for each of your buttons.

You may also want to take a look for existing solutions for at least part of the problem, such as node-keyboard: https://github.com/Bornholm/node-keyboard