Outputting with Willie bot doesn't work, but print does

Question

I am trying to return the output of a command to the IRC channel using Willie bot.

My code seems to work outputting my variable line by line, but for some reason once I utilize Willie bots say command to output to IRC it doesn't output anything.

Here is my code:

from willie import module
import subprocess
import urllib2
import os


@module.commands('splint')
def splint(bot, trigger):
    bot.reply('I will process your request now!')
    page = urllib2.urlopen(trigger.group(2))
    page_content = page.read();

    with open('codeToCheck.c', 'w') as code:
        code.write(page_content)

    command = 'splint "C:\Users\Justin\Desktop\codeToCheck.c"'
    output = subprocess.Popen(command,shell=True, stdout=subprocess.PIPE,stderr=subprocess.PIPE).communicate()[0]

    bot.say('I have saved the file successfully. Outputting:')

    for i in output.splitlines():
        bot.say(i)

    bot.say(output)

Using my little test code here I have determined it works with print:

import subprocess,os

output = subprocess.Popen(["splint", "C:\cygwin64\home\Justin\codeToCheck.c"], stdout=subprocess.PIPE).communicate()[0]

command = 'splint "C:\Users\Justin\Desktop\codeToCheck.c"'
output = subprocess.Popen(command,shell=True, stdout=subprocess.PIPE,stderr=subprocess.PIPE).communicate()[0]

for i in output.splitlines():
    print i

print 'I have saved the file successfully. Outputting:'

This is what the irc output looks like for my code:

<Fogest> .splint http://pastebin.com/raw.php?i=8cB7DdnQ
<Fogbot> Fogest: I will process your request now!
<Fogbot> I have saved the file successfully. Outputting:

There should be output, but there is nothing. Am I doing something wrong here? Running my test file (the test code I show on this post) via the command line I get the following output like I should:

$ python test.py
Splint 3.1.2 --- 25 Aug 2010

Finished checking --- no warnings
I have saved the file successfully. Outputting:

Answer 1

I switched the code to use the following instead:

process = subprocess.Popen(command,shell=True, stderr=subprocess.PIPE)
output = process.stderr.read()

The problem is now resolved.