Python user input in child process

问题:

I'm trying to create a child process that can take input through raw_input() or input(), but I'm getting an end of liner error EOFError: EOF when asking for input.

I'm doing this to experiment with multiprocessing in python, and I remember this easily working in C. Is there a workaround without using pipes or queues from the main process to it's child ? I'd really like the child to deal with user input.

def child():
    print 'test' 
    message = raw_input() #this is where this process fails
    print message

def main():
    p =  Process(target = child)
    p.start()
    p.join()

if __name__ == '__main__':
    main()

I wrote some test code that hopefully shows what I'm trying to achieve.

回答1:

My answer is taken from here: Is there any way to pass 'stdin' as an argument to another process in python?

I have modified your example and it seems to work:

from multiprocessing.process import Process
import sys
import os

def child(newstdin):
    sys.stdin = newstdin
    print 'test' 
    message = raw_input() #this is where this process doesn't fail anymore
    print message

def main():
    newstdin = os.fdopen(os.dup(sys.stdin.fileno()))
    p =  Process(target = child, args=(newstdin,))
    p.start()
    p.join()

if __name__ == '__main__':
    main()