python 进程间通信

from multiprocessing import Process,Value,Array
def fun(n,a):
    n.value = 3.1415927
    for i in range(len(a)):
        a[i] = -a[i]

if __name__ == '__main__':
    num = Value('d',0.0)
    arr = Array('i',range(10))
    p = Process(target=fun,args=(num,arr))
    p.start()
    p.join()
    print(num.value)
    print(arr[:])

from multiprocessing import Process,Manager
def fun(d,l):
    d[1]='1'
    d[2]=2
    d[0.25] = None
    l.reverse()

if __name__ == '__main__':
    with Manager() as manager:
        d = manager.dict()
        l = manager.list(range(10))
        p = Process(target=fun,args=(d,l))
        p.start()
        p.join()
        print(d)
        print(l)

 进程池

#！/usr/bin/env python
# -*- coding:utf-8 -*-
from multiprocessing import Pool
import time

def myfun(i):
    time.sleep(2)
    return i + 100
def end_call(arg):
    print('end_call'+ str(arg))
if __name__ == '__main__':
    p = Pool(5)
    for i in range(10):
        p.apply_async(func=myfun,args=(i,),callback=end_call)
    print('end')
    p.close()
    p.join()