process对象的其他属性或者方法

#join方法
import time, os
from multiprocessing import Process
def task(name, n):
    print('%s is running'%name)
    time.sleep(n)
if __name__ =='__main__':
    start = time.time()
    p1 = Process(target=task, args=('子进程1',5))
    p2 = Process(target=task, args=('子进程2',3))
    p3 = Process(target=task, args=('子进程3',2))
    p1.start()
    p2.start()
    p3.start()
    p1.join()  #此方法写时间不会累计时间（串行）
    p2.join()
    p3.join()
    print('主', time.time() - start)
    print(p1.pid)
    print(p2.pid)
    print(p3.pid)



import time, os
from multiprocessing import Process
def task(name, n):
    print('%s is running'%name)
    time.sleep(n)
if __name__ =='__main__':
    start = time.time()
    p1 = Process(target=task, args=('子进程1',5))
    p2 = Process(target=task, args=('子进程2',3))
    p3 = Process(target=task, args=('子进程3',2))
    p1.start()  #此方法写会累计时间（串行）
    p1.join()
    p2.start()
    p2.join()
    p3.start()
    p3.join()
    print('主', time.time() - start)
    print(p1.pid)
    print(p2.pid)
    print(p3.pid)



import time, os
from multiprocessing import Process
def task(name, n):
    print('%s is running'%name)
    time.sleep(n)
if __name__ =='__main__':
    start = time.time()
    p1 = Process(target=task, args=('子进程1',5))
    p2 = Process(target=task, args=('子进程2',3))
    p3 = Process(target=task, args=('子进程3',2))
    p_l = [p1, p2, p3]
    for p in p_l:
        p.start()
    for p in p_l:
        p.join()
    print('主', time.time() - start)
    print(p1.pid)
    print(p2.pid)
    print(p3.pid)
#了解  is_alive  判断进程是否存活
import time, os
from multiprocessing import Process
def task(name):
    print('%s is running'%name)
    time.sleep(3)
if __name__ =='__main__':
    start = time.time()
    p1 = Process(target=task, args=('子进程1',))
    p1.start()  #此方法写会累计时间（串行）
    print(p1.is_alive())
    p1.join()
    print('主', time.time() - start)
    print(p1.pid)
    print(p1.is_alive())


import time, os
from multiprocessing import Process
def task(name):
    print('%s is running'%name)
    time.sleep(3)
if __name__ =='__main__':
    p = Process(target=task, name = '我是进程名字', args=('子进程',))
    p.start() # 起动进程  （只是向操作系统发了命令 并非执行成功）
    p.join()  # 等待进程执行成功
    p.terminate()  #杀死进程
    print(p.is_alive())   # 判断进程是否活着
    print(p.name)   # 查看进程名字