多进程

import os
import time

ret=os.fork()
print("ret=%d"%ret)
if ret>0:
    #while(True):
        #print("1111111")
        print("    父进程%d"%os.getpid())
        time.sleep(1)
        print("    父进程结束")

else:
    while(True):
        #print("2222222")
        print("子进程%d  %d"%(os.getpid(),os.getppid()))

        time.sleep(5)
        print("子进程结束")

print("---over---")

import os
import time

g_num=100
ret=os.fork()
print("ret=%d"%ret)
if ret==0:
    g_num += 1
    time.sleep(1)
    print(g_num)

else:
    time.sleep(5)
    print(g_num)

print("---over---")

import os
import time


ret=os.fork()

if ret==0:
    print("1")

else:
    print("2")

ret=os.fork()

if ret==0:
    print("111")

else:
    print("222")

from multiprocessing import Process
import time

def test():
    for i in range(5):
        print("1")
        time.sleep(2)
p=Process(target=test)
p.start()
#p.join()              #阻塞主进程，从此处等待子进程p结束后往下执行，join里面可以加上timeout时间，超时时间
print("父进程结束")


#用Process创建的子进程，父进程等待所有的子进程结束后结束

#用fork创建的父进程结束，不受子进程影响

from multiprocessing import Process
import time

class MyNewProcess(Process):
    def run(self):
        time_start=time.time()
        for i in range(1,10):
            time.sleep(1)
            print("1")
        time_end=time.time()
        print("子程序运行时间：%d"%(time_end-time_start))

p=MyNewProcess()
p.start()
p.join(5)
print("主程序结束")

from multiprocessing import Pool
import os
import time
import random

def worker(msg):
    t_start=time.time()
    print("%d开始执行,进程号为%d"%(msg,os.getpid()))
    time.sleep(random.random()*2)
    t_end=time.time()
    print(msg,"   执行的时间为%0.2f"%(t_end-t_start))
p=Pool(3)
for i in range(0,10):
    print("创建第%d个任务"%i)
    p.apply_async(worker,(i,))
print("-----------start------------")
p.close()
p.join()
print("-----------end------------")

from multiprocessing import Process
from multiprocessing import Queue

import os
import time
import random

def read(q):
    while(True):
        if(not q.empty()):
            t=q.get(True)
            print("读出一个数据%s"%t)
            time.sleep(random.random())
        else:
            break
def write(q):
    for i in ['a','b','c','d','e','f','g']:
        q.put(i)
        print("添加%s到队列"%i)
        time.sleep(random.random())


if __name__=='__main__':
    q = Queue()
    pw=Process(target=write,args=(q,))
    pr=Process(target=read,args=(q,))
    pw.start()
    pw.join()

    pr.start()
    pr.join()

from multiprocessing import Pool
from multiprocessing import Manager

import os
import time
import random

def read(q):
    while(True):
        if(not q.empty()):
            t=q.get(True)
            print("读出一个数据%s"%t)
            time.sleep(random.random())
        else:
            break
def write(q):

    for i in ['a','b','c','d','e','f','g']:
        q.put(i)
        print("添加%s到队列"%i)
        time.sleep(random.random())


if __name__=='__main__':
    q = Manager().Queue()
    po=Pool()
    po.apply(read,(q,))
    po.apply(write,(q,))
    po.close()
    po.join()
    print("%d End"%os.getpid())

import os
from multiprocessing import Pool
from multiprocessing import Manager

#复制单个文件的函数，参数列表包括文件夹名称及路径，待复制的路径
def copy_file(name,oldfilepath,newfilepath,queue):
    fr=open(oldfilepath+'/'+name)
    fw=open(newfilepath+'/'+name,'w')

    content=fr.read()

    fw.write(content)
    fr.close()
    fw.close()
    queue.put(name)

def main():

    #提示输入要复制的文件夹及路径
    old_file_path=input("请输入要复制的文件夹路径")
    #创建一个文件夹“复件”，要求输入新路径
    new_file_path=old_file_path+"_复件"
    os.mkdir(new_file_path)
    #获取待复制文件夹的所有文件名
    filenames=os.listdir(old_file_path)
    #创建多进程进行复制
    p=Pool(5)
    print("进程池已准备好")
    q=Manager().Queue()
    print("进程间队列已准备好")
    for name in filenames:
        print("准备复制文件“%s”"%name)
        p.apply_async(copy_file,(name,old_file_path,new_file_path,q))
    #队列统计已复制的文件名及个数
    sum=len(filenames)
    wanchengnum=0
    while(wanchengnum<sum):
        q.get()
        wanchengnum+=1
        print("共%d个文件，已经复制%d个文件"%(sum,wanchengnum))

    p.close()
    p.join()
if __name__ == '__main__':
    main()