Question

我希望将一个命令的输出传递给另一个命令。命令1必须在命令1执行完成后运行，依此类推。我尝试使用'subprocess.Popen（）'的'wait'。但不知怎的，它不起作用。

有人可以帮我这个吗？

使用的代码：

proc= subprocess.Popen(['python27','scriptA.py',file],cwd="C:\pythonPrograms\\",stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
proc.wait()
sortedop= subprocess.Popen(['sort'],cwd="C:\pythonPrograms\\",stdout=subprocess.PIPE,stdin=proc.stdout, stderr=subprocess.STDOUT)
sortedop.wait()
countReducer= subprocess.Popen(['python27', 'scriptB.py'],cwd="C:\pythonPrograms\\",stdout=subprocess.PIPE,stdin=sortedop.stdout, stderr=subprocess.STDOUT)
countReducer.wait()
fd = open(file+".json", 'w')
countpostprocesser= subprocess.Popen(['python27', 'scriptC.py'],cwd="C:\pythonPrograms\\",stdout=fd,stdin=countReducer.stdout,stderr=subprocess.STDOUT,shell=True)
countpostprocesser.wait()
fd.close()

Answer 1

如果你真的希望在下一个脚本启动之前完成一个脚本并且输出数据不是太大，你可以将数据读入内存：

proc= subprocess.Popen(['python27','scriptA.py',file],cwd="C:\\pythonPrograms\\",stdout=subprocess.PIPE, stderr=subprocess.PIPE)
out, err = proc.communicate()
sortedop= subprocess.Popen(['sort'],cwd="C:\pythonPrograms\\",stdout=subprocess.PIPE,stdin=subprocess.PIPE, stderr=subprocess.STDOUT)
out, err = sortedop.communicate(out)
countReducer= subprocess.Popen(['python27', 'scriptB.py'],cwd="C:\pythonPrograms\\",stdout=subprocess.PIPE, stdin=subprocess.PIPE, stderr=subprocess.STDOUT)
out, err = countReducer.communicate(out)
fd = open(file+".json", 'w')
countpostprocesser= subprocess.Popen(['python27', 'scriptC.py'],cwd="C:\pythonPrograms\\",stdout=fd, stderr=subprocess.STDOUT)
out, err = countpostprocesser.communicate(out)

在subprocess.Popen中使用管道

1 个答案: