Raw_input inside a Python process

问题:

I have created a small script in python where I want to execute two function on the same time using multiprocessing. The first function would do a directory recursive search and the second one will display some questions to the user. Although the .txt file is created the question doesn't appear. I have seen this question: Python command line input in a process but as a beginner I did not understand what is the problem and how to solve it. Here's my script:

import os
import thread
import time
from multiprocessing import Process

def writeFiles():
    #open a file for writing files in it
    f = open("testFile.txt","w")
    #do the walk
    for root ,dirs,files in os.walk('C:\\Users'):
        for dir in dirs:        
            if dir.startswith('Test'):
                for root ,dirs,files in os.walk('C:\\Users\\' + dir +'\Desktop'):
                    for file in files:
                        if file.endswith('.txt'):                        
                            #include the full path
                            f.write( os.path.join(root, file + "\n") )

    #close the file
    f.close()

def ask():
    a = raw_input('Your name? ')
    if a == 'Tester':
        print 'Hello'
    else:
        print 'Bye'   


if __name__ == '__main__':   

# create processes
p1 = Process( target = writeFiles)
p2 = Process( target = ask)
p1.start()
p2.start()

回答1:

The simplest thing to do would be to call ask from the main process itself:

if __name__ == '__main__': 
    p1 = Process(target = writeFiles)   
    p1.start()
    ask()

Or you could use a thread:

import threading
import multiprocessing as mp
import sys

def ask(stdin):
    print 'Your name? ',
    a = stdin.readline().strip()
    if a == 'Tester':
        print 'Hello'
    else:
        print 'Bye'   
    stdin.close()

def writeFiles():
    pass

if __name__ == '__main__': 
    p1 = mp.Process(target=writeFiles)   
    p1.start()
    t1 = threading.Thread(target=ask, args=(sys.stdin,))
    t1.start()
    p1.join()
    t1.join()

---

Or, you could use os.dup as J.F. Sebastian shows here:

import multiprocessing as mp
import sys
import os

def ask(stdin):
    print 'Your name? ',
    a = stdin.readline().strip()
    if a == 'Tester':
        print 'Hello'
    else:
        print 'Bye'   
    stdin.close()

def writeFiles():
    pass

newstdin = os.fdopen(os.dup(sys.stdin.fileno()))

if __name__ == '__main__': 
    p1 = mp.Process(target=writeFiles)   
    p1.start()
    p2 = mp.Process(target=ask, args=(newstdin,))
    p2.start()
    p1.join()
    p2.join()