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Python subprocess output to windows?

I am facing some difficulties getting output from the stdout pipe subprocess. I run some third-party code through it to extract the output from the log. Until a recent third-party code update, everything worked fine. After the upgrade, python started the lock indefinitely and did not actually show any output. I can start the third-party application manually and see the output.

Basic version of the code used:

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("\r\n")
        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)

This works fine if I replace the third_party.exe file for this script:

import time, sys

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

So, I don't know how magic is needed for this to work with the original team.

These are all subprocess options. Staging I tried without success:

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

1: .communicate(). , , ( ). , .communicate(), - , , , .

:

import subprocess, time
from threading import Thread

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

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

2: jdi, :

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()
+5
2

, , - . :

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

, . , stdout , , .

, stderr stdout?

proc = subprocess.Popen("third_party.exe", 
                        stdout=subprocess.PIPE, 
                        stderr=subprocess.STDOUT, bufsize=1)

, communicate() , , , ...

import tempfile
import subprocess

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

with open(w.name, 'r') as r:
    for line in r:
        print line
w.close()
+5
args = ['svn','log','-v']

def foo(info=''):
    import logging
    import subprocess
    import tempfile
    try:
        pipe = subprocess.Popen(args,bufsize = 0,\
            stdout = subprocess.PIPE,\
            stderr=subprocess.STDOUT)
    except Exception as e:
        logging.error(str(e))
        return False
    while 1:
        s = pipe.stdout.read()
        if s:
            print s,
        if pipe.returncode is None:
            pipe.poll()
        else:
            break
    if not 0 == pipe.returncode:
        return False
    return True

print foo()

, , temp file magic.

+2

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