#!/usr/bin/python
import sys, os, select, time

i = 0

def getInput():
	input = ''
	while len(select.select([sys.stdin.fileno()], [], [], 0.0)[0])>0:
		input += os.read(sys.stdin.fileno(), 4096)
	return input

def doWork():
	global i
	time.sleep(0.5)
	i += 1

if __name__=='__main__':
	input = ''
	while not input:
		doWork()
		input = getInput()
	print "got user input: %r" % input
	print "did %d units of work" % i