import os, commands

def test_1():
    try:
        n = int(os.popen('pidof pigpiod').read().splitlines()[0])
    except:
        n = None
    return n

def test_2():
    try:
        n = int(commands.getstatusoutput('pidof pigpiod')[1])
    except:
        n = None
    return n

print "test 1: ", test_1()
print "test 2: ", test_2()

test 1:  2038
test 2:  2038

test 1:  None
test 2:  None