Python基础进程和线程 一 背景知识

import multiprocessing
import time

def worker(interval):
    print("work start:{0}".format(time.ctime()))
    time.sleep(interval)
    print("work end:{0}".format(time.ctime()))

if __name__ == "__main__":
    p = multiprocessing.Process(target = worker, args = (3,))
    p.daemon=True
    p.start()
    print ("end!")

# end!

from socket import *
from multiprocessing import Process

server=socket(AF_INET,SOCK_STREAM)
server.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
server.bind(('127.0.0.1',8080))
server.listen(5)

def talk(conn,client_addr):
    while True:
        try:
            msg=conn.recv(1024)
            if not msg:break
            conn.send(msg.upper())
        except Exception:
            break

if __name__ == '__main__': #windows下start进程一定要写到这下面
    while True:
        conn,client_addr=server.accept()
        p=Process(target=talk,args=(conn,client_addr))
        p.start()

from socket import *

client=socket(AF_INET,SOCK_STREAM)
client.connect(('127.0.0.1',8080))


while True:
    msg=input('>>: ').strip()
    if not msg:continue

    client.send(msg.encode('utf-8'))
    msg=client.recv(1024)
    print(msg.decode('utf-8'))

from multiprocessing import Process
import time
# import random
def piao(name):
    print('%s is piaoing' % name)
    time.sleep(1)
    print('%s is piao end' % name)
if __name__ == '__main__':
    p1=Process(target=piao,args=('egon',))
    p2=Process(target=piao,args=('alex',))
    p3=Process(target=piao,args=('wupeiqi',))
    p4=Process(target=piao,args=('yuanhao',))

    p_l=[p1,p2,p3,p4]
    for p in p_l:
        p.start()
    for p in p_l:
        p.join()
    print('主进程')

from multiprocessing import Process
import time
import random
def piao(name):
    print('%s is piaoing' % name)
    time.sleep(random.randint(1,3))
    print('%s is piao end' % name)
if __name__ == '__main__':
    p1=Process(target=piao,args=('egon',))
    p1.daemon=False #默认值为False，如果设为True，代表p为后台运行的守护进程，当p的父进程终止时，p也随之终止，并且设定为True后，p不能创建自己的新进程，必须在p.start()之前设置
    p1.start()
    p1.terminate()#强制终止进程p，不会进行任何清理操作，如果p创建了子进程，该子进程就成了僵尸进程，使用该方法需要特别小心这种情况。如果p还保存了一个锁那么也将不会被释放，进而导致死锁
    print(p1.is_alive())#如果p仍然运行，返回True
    time.sleep(1)
    print(p1.is_alive())#如果p仍然运行，返回True
    print('主进程')
    print(p1.name) #为子进程的名称
    print(p1.pid) #进程的pid

'''
multiprocessing模块支持进程间通信的两种主要形式:管道和队列
都是基于消息传递实现的,但是队列接口
'''

from multiprocessing import Process,Queue
import time
q=Queue(3)


#put ,get ,put_nowait,get_nowait,full,empty
q.put(3)
q.put(3)
q.put(3)
print(q.full()) #满了

print(q.get())
print(q.get())
print(q.get())
print(q.empty()) #空了

from multiprocessing import Process,Queue #队列模块
import time
import random

def consumer(q,name):
    while True:
        time.sleep(random.randint(1,3))
        res=q.get() #从队列读取并且删除一个元素
        print('