How do I 'lock the keyboard' to prevent any more keypresses being sent on X11/Linux/Gnome?

Question

I am writing an anti-RSI/typing break programme for Ubuntu Linux in python. I would like to be able to "lock the keyboard" so that all keypresses are ignored until I "unlock" it. I want to be able to force the user to take a typing break.
I would like some programmatic way to "turn off" the keyboard (near instantaneously) until my programme releases it later (which could be 0.1 sec → 10 sec later). While I have "turned off the keyboard", no key presses should be sent to any
windows, window managers, etc. Preferably, the screen should still show the same content. The keyboard should be locked even if this programme is not at the forefont and does not have focus.
Some programmes are able to do this already (e.g. Work Rave)
How do I do this on Linux/X11? (Preferable in Python)

Answer 1

class KeyboardLocker:
def __init__(self, serio=0):
self._on = False
self.serio = serio
def on(self):
return self._on
def write_value(self,path, value):
with open(path, "a") as f:
f.write(value)
def toggle(self):
if self.on():
self.turn_off()
else:
self.turn_on()
def description(self):
path = '/sys/devices/platform/i8042/serio%d/description' % (self.serio,)
with open(path, "r") as f:
description = f.read()
return description
def turn_on(self):
try:
self.write_value('/sys/devices/platform/i8042/serio%d/bind_mode' % (self.serio,),
'auto')
except IOError, e:
self._on = False
raise
else:
self._on = True
return self.on()
def turn_off(self):
try:
self.write_value('/sys/devices/platform/i8042/serio%d/bind_mode' % (self.serio,),
'manual')
self.write_value('/sys/devices/platform/i8042/serio%d/drvctl' % (self.serio,),
'psmouse')
except IOError, e:
self._on = True
raise
else:
self._on = False
return self.on()
if __name__ == "__main__":
kl = KeyboardLocker(serio=0)
device = kl.description()
print "We got a lock on", device
proceed = raw_input("Do you want to proceed? (y/n)").lower().startswith("y")
import sys
if not proceed: sys.exit(1)
kl.turn_off()
import time
wait = 5
print "Sleeping few seconds...", wait
time.sleep(wait)
print "Voila!"
kl.turn_on()
raw_input("Does it work now?")
Tested on Linux Mint 12, X11, HP Laptop, Gnome. Not sure if any of that matters though :)
UPDATE Added an option to change the path, e.g. "serio0" or "serio1". And prints the description, for me serio0 gave me: i8042
KBD port, most likely if you have "KBD" in it, it's right, continue, otherwise I give you no guarantee :)