Example of using /dev/input/event* (piped to stdin) for handling keyboard shortcuts.

shortcuts.py

#!/usr/bin/env python3

from json import load
from os import read
from struct import Struct
from subprocess import call
from sys import argv, stdin
from time import sleep

def main(config_file):
    struct = Struct('llHHI')
    with open(config_file, 'r') as config_file:
        config = load(config_file)
    with stdin as input:
        events, per_round, latest_event_time, pressed = '', 2 ** 10 , 0, set()
        while events or latest_event_time == 0:
            sleep(3)
            events = read(input.fileno(), struct.size * per_round)
            if len(events) == struct.size * per_round and per_round < 2 ** 20:
               per_round *= 2
            for event in partitions(events, struct.size):
                tv_sec, _, type, code, value = struct.unpack(event)
                if latest_event_time + 3 < tv_sec:
                    pressed = set()
                latest_event_time = tv_sec
                previous = pressed.copy()
                if type == 1 and value != 0:
                    pressed.add(code)
                elif type == 1 and value == 0:
                    pressed.discard(code)
                key_sequence = ' + '.join(map(str, sorted(pressed)))
                if previous != pressed and key_sequence in config:
                    call(config.get(key_sequence))


def partitions(list, chunk_size):
    assert len(list) % chunk_size == 0, "Equal partitons"
    return (list[i:i + chunk_size] for i in range(0, len(list), chunk_size))


if __name__ == '__main__':
    assert len(argv) > 1, "Usage:\t%s <configuration file>" % argv[0]
    main(argv[1])