Windows上的Python子进程输出？

我在从子进程stdout管道获取输出时遇到了一些困难.我正在通过它启动一些第三方代码,以便提取日志输出.直到最近更新第三方代码,一切正常.更新后,python已无限期地开始阻塞,并且实际上没有显示任何输出.我可以手动启动第三方应用程序并查看输出.

我正在使用的代码的基本版本：

import subprocess,time
from threading import Thread

def enqueue_output(out):
    print "Hello from enqueue_output"
    for line in iter(out.readline,''):
        line = line.rstrip("rn")
        print "Got %s" % line
    out.close()

proc = subprocess.Popen("third_party.exe",stdout=subprocess.PIPE,bufsize=1)
thread = Thread(target=enqueue_output,args=(proc.stdout,))
thread.daemon = True
thread.start()

time.sleep(30)

如果我将third_party.exe替换为此脚本,则此方法非常有效：

import time,sys

while True:
    print "Test"
    sys.stdout.flush()
    time.sleep(1)

所以我不清楚魔法需要做什么才能使用原始命令.

这些都是subprocess.Popen行的所有变种我试过没有成功：

proc = subprocess.Popen("third_party.exe",bufsize=0)
proc = subprocess.Popen("third_party.exe",shell=True)
proc = subprocess.Popen("third_party.exe",creationflags=subprocess.CREATE_NEW_CONSOLE)
si = subprocess.STARTUPINFO()
si.dwFlags = subprocess.STARTF_USESTDHANDLES | subprocess.STARTF_USESHOWWINDOW
proc = subprocess.Popen("third_party.exe",startupinfo=si)

编辑1：
在这种情况下,我实际上无法使用.communicate().我正在推出的应用程序仍然运行很长一段时间(几天到几周).我实际测试.communicate()的唯一方法就是在启动后立即杀死应用程序,我觉得不会给我有效的结果.

即使非线程版本也失败了：

import subprocess,time
from threading import Thread

proc = subprocess.Popen("third_party.exe",stderr=subprocess.PIPE)

print "App started,reading output..."
for line in iter(proc.stdout.readline,''):
    line = line.rstrip("rn")
    print "Got: %s" % line

编辑2：
感谢jdi,以下工作正常：

import tempfile,time,subprocess

w = "test.txt"
f = open("test.txt","a")
p = subprocess.Popen("third_party.exe",shell=True,stdout=f,stderr=subprocess.STDOUT,bufsize=0)

time.sleep(30)

with open("test.txt",'r') as r:
    for line in r:
        print line
f.close()

proc = subprocess.Popen("third_party.exe",bufsize=1)
print proc.communicate()

proc = subprocess.Popen("third_party.exe",bufsize=1)

import tempfile
import subprocess

w = tempfile.NamedTemporaryFile()
p = subprocess.Popen('third_party.exe',stdout=w,bufsize=0)

with open(w.name,'r') as r:
    for line in r:
        print line
w.close()