python之进程

Posted 2020-10-26 Claire_xu

 

开启子进程的两种方式：

1、使用Process类

from multiprocessing import Process
import time,os

def f(name):
    print(‘%s is running,parent id is <%s>‘%(os.getpid(),os.getppid()),time.ctime())
    time.sleep(1)
    print(‘%s is done‘ % os.getpgid(), time.ctime())

if __name__ == ‘__main__‘:
    p_list=[]
    for i in range(3):
        p = Process(target=f, args=(‘子进程%s‘%i,))
        # p = Process(target=f,kwargs={‘name‘:‘子进程%s‘%i})
        p_list.append(p)
        p.start()  # 仅仅是给操作系统发送了一个信号
    print(‘主进程‘,os.getpid())
    for i in p_list:
        p.join()
    print(‘end‘)

 

2、写子类继承Process类

from multiprocessing import Process
import time

class MyProcess(Process):
    def __init__(self,name):
        super(MyProcess, self).__init__()
        self.name = name

    def run(self):
        print(‘%s is running‘ % self.name, time.ctime())
        time.sleep(1)
        print(‘%s is done‘ % self.name, time.ctime())


if __name__ == ‘__main__‘:
    p_list=[]
    for i in range(3):
        p = MyProcess(‘子进程%d‘%i)
        p.start()
        p_list.append(p)
    for p in p_list:
        p.join()
    print(‘end‘)