_name_ == "_main_" 多进程在windows和linux下的差异

name == "main" 多进程在windows和linux下的差异

windows报错 linux成功

import multiprocessing as mp
 
def ParameterCalculation(list,output):
    output.put(1)
 
result = 0
if __name__ == "__main__":
    output = mp.Queue()
    processes = []
    processes.append(mp.Process(target=ParameterCalculation, args=([], output)))
    processes.append(mp.Process(target=ParameterCalculation, args=([], output)))
    for p in processes:
        p.start()
    resultMp = [output.get() for p in processes]
    for p in processes:
        p.join()
    for j in range(0, len(resultMp)):
        result = result + resultMp[j]
 
FreYield = round((1212 / float(result)) * 100, 4)
print(FreYield)

windows成功 linux成功

import multiprocessing as mp
 
def ParameterCalculation(list,output):
    output.put(1)
 
result = 0
if __name__ == "__main__":
    output = mp.Queue()
    processes = []
    processes.append(mp.Process(target=ParameterCalculation, args=([], output)))
    processes.append(mp.Process(target=ParameterCalculation, args=([], output)))
    for p in processes:
        p.start()
    resultMp = [output.get() for p in processes]
    for p in processes:
        p.join()
    for j in range(0, len(resultMp)):
        result = result + resultMp[j]
FreYield = round((1212 / float(result)) * 100, 4)
print(FreYield)

windows的多进程和Linux的多进程的创建形式不同，windows的多进程通过导入模块实现，不在main函数内的代码会被在子进程中再次执行，而linux的多线程是通过fork来创建子进程，可以按照代码顺序执行下去