如何同步Python子进程的输出

发布于 2024-09-08 20:28:02 字数 1017 浏览 3 评论 0原文

我认为我在同步同时运行的两个 Popen 的输出时遇到问题。看起来这两个不同命令行的输出是相互交错的。我也尝试使用 RLock 来防止这种情况发生，但没有成功。

示例输出如下：

cmd1
cmd1
cmd2
cmd2
cmd2
cmd2
cmd1
cmd2

代码如附件所示：

import subprocess
import threading

class PopenWorkerThread(threading.Thread):
    def __init__(self, cmdLine):
        self.lock = threading.RLock()
        self.WebSphereCmdLine = cmdLine
        threading.Thread.__init__(self)

    def run(self):
        logger.error('Runninf: ' + self.WebSphereCmdLine)
        proc = subprocess.Popen(self.WebSphereCmdLine, shell=False, stdout=subprocess.PIPE)
        while True:
            self.lock.acquire()
            print proc.stdout.readline()
            self.lock.release()

def launch():
    commandLine = ['ls -l', 'netstat']
    for cmdLine in commandLine:
        workerThread = PopenWorkerThread(cmdLine)
        workerThread.start()

launch()

有没有办法同步输出，使它们看起来像这样？

cmd1
cmd1
cmd1
cmd1
cmd1
cmd2
cmd2
cmd2
cmd2
cmd2

原文

I think I'm having issues to synchronize the output of two Popen running concurrently. It seems that the output from these two different command lines are interleaved with one another. I also tried using RLock to prevent this from happening but it didn't work.

A sample output would be:

cmd1
cmd1
cmd2
cmd2
cmd2
cmd2
cmd1
cmd2

The code is as attached:

import subprocess
import threading

class PopenWorkerThread(threading.Thread):
    def __init__(self, cmdLine):
        self.lock = threading.RLock()
        self.WebSphereCmdLine = cmdLine
        threading.Thread.__init__(self)

    def run(self):
        logger.error('Runninf: ' + self.WebSphereCmdLine)
        proc = subprocess.Popen(self.WebSphereCmdLine, shell=False, stdout=subprocess.PIPE)
        while True:
            self.lock.acquire()
            print proc.stdout.readline()
            self.lock.release()

def launch():
    commandLine = ['ls -l', 'netstat']
    for cmdLine in commandLine:
        workerThread = PopenWorkerThread(cmdLine)
        workerThread.start()

launch()

Is there a way to synchronize the outputs so that they look like such?

cmd1
cmd1
cmd1
cmd1
cmd1
cmd2
cmd2
cmd2
cmd2
cmd2

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

々眼睛长脚气 2024-09-15 20:28:02

也许您正在寻找等待方法

http://docs.python。 org/library/subprocess.html#subprocess.Popen.wait

回复收藏 0 原文

孤者何惧 2024-09-15 20:28:02

您以行的粒度进行锁定，因此一个线程中的行当然可以并且确实与另一个线程中的行交替。只要您愿意等到进程结束后再显示其任何输出，您就可以使用更大的“进程”粒度进行锁定。当然，您必须对两个线程使用相同的锁——让每个线程使用完全独立的锁，就像您现在所做的那样，显然根本无法实现任何目标。

因此，例如：

import subprocess
import threading

class PopenWorkerThread(threading.Thread):

    lock = threading.RLock()  # per-class, NOT per-instance!

    def __init__(self, cmdLine):
        self.WebSphereCmdLine = cmdLine
        threading.Thread.__init__(self)

    def run(self):
        logger.error('Runninf: ' + self.WebSphereCmdLine)
        proc = subprocess.Popen(self.WebSphereCmdLine, shell=False, stdout=subprocess.PIPE)
        result, _ = proc.communicate()
        with self.lock:
            print result,

def launch():
    commandLine = ['ls -l', 'netstat']
    for cmdLine in commandLine:
        workerThread = PopenWorkerThread(cmdLine)
        workerThread.start()

launch()

You're locking with a granularity of a line, so of course lines from one thread can and do alternate with lines from the other. As long as you're willing to wait until a process ends before showing any of its output, you can lock with the larger "process" granularity. Of course you have to use the SAME lock for both threads -- having each thread use a completely separate lock, as you're doing now, cannot achieve anything at all, obviously.

So, for example:

import subprocess
import threading

class PopenWorkerThread(threading.Thread):

    lock = threading.RLock()  # per-class, NOT per-instance!

    def __init__(self, cmdLine):
        self.WebSphereCmdLine = cmdLine
        threading.Thread.__init__(self)

    def run(self):
        logger.error('Runninf: ' + self.WebSphereCmdLine)
        proc = subprocess.Popen(self.WebSphereCmdLine, shell=False, stdout=subprocess.PIPE)
        result, _ = proc.communicate()
        with self.lock:
            print result,

def launch():
    commandLine = ['ls -l', 'netstat']
    for cmdLine in commandLine:
        workerThread = PopenWorkerThread(cmdLine)
        workerThread.start()

launch()

回复收藏 0 原文

~没有更多了~