Python多进程函数无返回值问题：游戏逻辑无法终止主进程

我是一名中学生，正在开发一款仅用Python打印输出的游戏，需要用到multiprocessing多进程功能，但游戏函数里有input()输入操作，不能放进多进程否则会报错。现在的问题是，我期望timer或play函数任意一个结束后就能终止主进程，让两者同时运行，但实际函数返回后程序还会继续执行，最终打印出None。

原代码 #

import multiprocessing
import time
import random
g = "Something from the list: "
def timer(seconds):
    print(f"Sleeping for {seconds} second(s)")
    time.sleep(seconds)
    print( )
    return "Done sleeping"
def anything(y):
    print(y)
def play(thing,harga):
        while True:
            t = thing
            price = harga[f"{thing}"]
            y = "-"
            h_1 = 54
            h = random.randint(0,h_1)
            if h == 0:
                print(f"{t:{y}<{h_1+len(t)}}")
                ans = input("Do something!:  ")
                if ans == thing:
                    print(f"Great the price is {price} Credits!")
                    return "True"
            else:
                h1 = (h_1 - h)
                print(f"{y:{y}<{h}}{t:{y}<{h1 + len(t)}}")
                ans = input("Do something!:  ")
                if ans == thing:
                    print(f"Great the price is {price} Credits!")
                    return "True"
    
def idk( ):
        time.sleep(0.1)
        list = ["Cheese","Pickle"]
        y = random.choice(list)
        anything(y)
        prilist = {"Cheese": 100,"Pickle":50}
        play(y,prilist)
p1 = multiprocessing.Process(target=timer,args=[3])
def play1( ):
        v = p1.start( )
        if v == "Done sleeping":
            return "Gagal"
        v2 = idk( )
        if v2 == "True":
            return "True"
        p1.join( )
print(play1( ))

原程序输出 #

Sleeping for 3 second(s)

Cheese

---------------Cheese---------------------------------------Do something!:  Cheese

Great the price is 100 Credits!

None

[Program finished]

解决方案 #

问题分析 #

1. p1.start()不会返回进程的返回值，v == "Done sleeping"永远不成立
2. idk()函数未返回play()的执行结果，导致v2始终为None，最终play1()无返回值，打印None
3. 未监听两个任务的完成状态，无法实现任意任务结束后终止主进程

修改后的代码 #

import multiprocessing
import time
import random

g = "Something from the list: "

def timer(seconds, done_event):
    print(f"Sleeping for {seconds} second(s)")
    time.sleep(seconds)
    print()
    # 触发事件通知主进程：timer已完成
    done_event.set()
    return "Done sleeping"

def anything(y):
    print(y)

def play(thing, harga, done_event):
    while True:
        t = thing
        price = harga[f"{thing}"]
        y = "-"
        h_1 = 54
        h = random.randint(0, h_1)
        if h == 0:
            print(f"{t:{y}<{h_1+len(t)}}")
        else:
            h1 = (h_1 - h)
            print(f"{y:{y}<{h}}{t:{y}<{h1 + len(t)}}")
        
        ans = input("Do something!:  ")
        if ans == thing:
            print(f"Great the price is {price} Credits!")
            # 触发事件通知主进程：play已完成
            done_event.set()
            return "True"

def idk(done_event):
    time.sleep(0.1)
    item_list = ["Cheese","Pickle"]
    y = random.choice(item_list)
    anything(y)
    prilist = {"Cheese": 100,"Pickle":50}
    # 返回play函数的执行结果
    return play(y, prilist, done_event)

def play1():
    # 创建进程间通信的事件对象
    done_event = multiprocessing.Event()
    
    # 启动timer进程，传入事件对象
    p1 = multiprocessing.Process(target=timer, args=[3, done_event])
    p1.start()
    
    # 在主进程执行play任务（避免input放入多进程报错）
    play_result = idk(done_event)
    
    # 等待任意一个任务触发完成事件
    done_event.wait()
    
    # 终止未完成的进程
    if p1.is_alive():
        p1.terminate()
        p1.join()
    
    # 返回对应结果
    return "True" if play_result == "True" else "Gagal"

print(play1())

修改说明 #

1. 用multiprocessing.Event()实现进程间通信：timer和play完成时都会触发事件，主进程通过wait()监听，任意任务完成就会终止等待
2. 修复idk()的返回值问题，让它传递play()的结果，确保play1()能拿到有效返回值
3. 事件触发后，主动终止未完成的进程，避免无效执行
4. 保留play()在主进程执行，规避input()放入多进程的报错问题

内容的提问来源于stack exchange，提问作者user24159246