手把手带你了解python多进程,多线程

import time
import multiprocessing
import os
def dance(who,num):
 print("dance父进程：{}".format(os.getppid()))
 for i in range(1,num+1):
  print("进行编号：{}————{}跳舞。。。{}".format(os.getpid(),who,i))
  time.sleep(0.5)
def sing(num):
 print("sing父进程：{}".format(os.getppid()))
 for i in range(1,num+1):
  print("进行编号：{}----唱歌。。。{}".format(os.getpid(),i))
  time.sleep(0.5)
def work():
 for i in range(10):
  print("工作中。。。")
  time.sleep(0.2)
if __name__ == '__main__':
 # print("main主进程{}".format(os.getpid()))
 start= time.time()
 #1 进程的创建与启动
 # # 1.1创建进程对象，注意dance不能加括号
 # # dance_process = multiprocessing.Process(target=dance)#1.无参数
 # dance_process=multiprocessing.Process(target=dance,args=("lin",3))#2.以args=元祖方式
 # sing_process = multiprocessing.Process(target=sing,kwargs={"num":3})#3.以kwargs={}字典方式
 # # 1.2启动进程
 # dance_process.start()
 # sing_process.start()
 #2.默认-主进程和子进程是分开的，主进程只要1s就可以完成，子进程要2s，主进程会等所有子进程执行完，再退出
 # 2.1子守护主进程,当主一但完成，子就断开(如qq一关闭，所有聊天窗口就没了).daemon=True
 work_process = multiprocessing.Process(target=work,daemon=True)
 work_process.start()
 time.sleep(1)
 print("主进程完成了！")#主进程和子进程是分开的，主进程只要1s就可以完成，子进程要2s，主进程会等所有子进程执行完，再退出
 print("main主进程花费时长：",time.time()-start)
 #

import time
import os
import threading
def dance(num):
 for i in range(num):
  print("进程编号：{}，线程编号：{}————跳舞。。。".format(os.getpid(),threading.current_thread()))
  time.sleep(1)
def sing(count):
 for i in range(count):
  print("进程编号：{}，线程编号：{}----唱歌。。。".format(os.getpid(),threading.current_thread()))
  time.sleep(1)
def task():
 time.sleep(1)
 thread=threading.current_thread()
 print(thread)
if __name__ == '__main__':
 # start=time.time()
 # # sing_thread =threading.Thread(target=dance,args=(3,),daemon=True)#设置成守护主线程
 # sing_thread = threading.Thread(target=dance, args=(3,))
 # dance_thread = threading.Thread(target=sing,kwargs={"count":3})
 #
 # sing_thread.start()
 # dance_thread.start()
 #
 # time.sleep(1)
 # print("进程编号：{}主线程结束...用时{}".format(os.getpid(),(time.time()-start)))
 for i in range(10):#多线程之间执行是无序的，由cpu调度
  sub_thread = threading.Thread(target=task)
  sub_thread.start()

import threading
import time
lock =threading.Lock()
class Sum_tickets:
 def __init__(self,tickets):
  self.tickets=tickets
def window(sum_tickets):
 while True:
  with lock:
if sum_tickets.tickets>0:
 time.sleep(0.2)
 print(threading.current_thread().name,"取票{}".format(sum_tickets.tickets))
 sum_tickets.tickets-=1
else:
 break
if __name__ == '__main__':
 sum_tickets=Sum_tickets(10)
 sub_thread1 = threading.Thread(name="窗口1",target=window,args=(sum_tickets,))
 sub_thread2 = threading.Thread(name="窗口2",target=window,args=(sum_tickets,))
 sub_thread1.start()
 sub_thread2.start()

import os
import multiprocessing
import threading
import time
def copy_file(file_name,source_dir,dest_dir):
 source_path = source_dir+"/"+file_name
 dest_path =dest_dir+"/"+file_name
 print("当前进程为：{}".format(os.getpid()))
 with open(source_path,"rb") as source_file:
  with open(dest_path,"wb") as dest_file:
while True:
 data=source_file.read(1024)
 if data:
  dest_file.write(data)
 else:
  break
 pass
if __name__ == '__main__':
 source_dir=r'C:\Users\Administrator\Desktop\注意力'
 dest_dir=r'C:\Users\Administrator\Desktop\test'
 start = time.time()
 try:
  os.mkdir(dest_dir)
 except:
  print("目标文件已存在")
 file_list =os.listdir(source_dir)
 count=0
 #1多进程
 for file_name in file_list:
  count+=1
  print(count)
  sub_processor=multiprocessing.Process(target=copy_file,
 args=(file_name,source_dir,dest_dir))
  sub_processor.start()
  # time.sleep(20)
 print(time.time()-start)
#这里有主进程和子进程，通过打印可以看出，主进程在创建1，2，3，4，，，21过程中，子进程已有的开始执行，也就是说，每个进程是互不影响的
# 9
# 10
# 11
# 12
# 13
# 当前进程为：2936(当主进程创建第13个时，此时，第一个子进程开始工作)
# 14
# 当前进程为：10120
# 当前进程为：10440
# 15
# 当前进程为：9508
 # 2多线程
 # for file_name in file_list:
 #  count += 1
 #  print(count)
 #  sub_thread = threading.Thread(target=copy_file,
 #  args=(file_name, source_dir, dest_dir))
 #  sub_thread.start()
 #  # time.sleep(20)
 # print(time.time() - start)