0704 Process继承实现多进程、Pool进程池，及Pool实现多进程实现复制文件

通过继承的方式，实现Process多进程

 1 from multiprocessing import Process
 2 import time
 3
 4 class MyNewProcess(Process):
 5     def run(self):
 6         for i in range(10):
 7             print("----run----")
 8             time.sleep(1)
 9
10
11 if __name__ == "__main__":
12     p = MyNewProcess()
13
14     p.start()        # Process 中的 start 方法会主动调用 run 方法
15 for i in range(10): print("---main---") time.sleep(1)

Pool 进程池实现多进程

 1 import time
 2 from multiprocessing import Pool
 3
 4 def worker():
 5     for i in range(10):
 6         print("From worker %s"%i)
 7         time.sleep(0.5)
 8
 9 def foo():
10     for i in range(10):
11         print("From foo %s"%i)
12         time.sleep(0.5)
13
14 def bar():
15     for i in range(10):
16         print("From bar %s"%i)
17         time.sleep(0.5)
18
19 if __name__ == "__main__":
20     pool = Pool(3)            # 创建三个 进程
21     pool.apply_async(worker)
22     pool.apply_async(foo)
23     pool.apply_async(bar)
24
25     pool.close()                  # 关闭进程池，禁止添加任务
26     pool.join()          # 等待子进程结束后，主进程才往下走
27     print("Is done...")
28
29
30
31 # process and Pool 最后都是调用 fork
32 # 通常情况下，主进程一半用来等低啊，，，，真正的任务子进程中执行

利用Pool进程池实现简单的文件复制

 1 import os
 2 import time
 3 from multiprocessing import Pool
 4
 5 def copyFile(oldPath, newPath, fileName):
 6     print("%s 准备复制中。。。"%fileName)
 7     with open("%s\%s"%(oldPath, fileName), ‘r‘) as fr, open("%s\%s"%(newPath, fileName), ‘w‘) as fw:
 8         for line in fr:
 9             fw.write(line)
10     time.sleep(1)
11
12
13 if __name__ == "__main__":
14     oldPath = r"file"
15     newPath = r"file-副本"
16
17     os.mkdir(newPath)
18
19     pool = Pool(5)
20
21     fileList = os.listdir(oldPath)
22
23     for fileName in fileList:
24         pool.apply_async(copyFile, (oldPath, newPath, fileName))
25
26     pool.close()
27
28     pool.join()
29
30     print("文件复制完成....")