【python】多任务编程之线程、进程知识点详细总结

1. import multiprocessing
2. import time
3. def sing():
4. for i in range(3):
5. print(f"唱歌第{i}次")
6.         time.sleep(0.2)
7. def dance():
8. for i in range(3):
9. print(f"跳舞第{i}次")
10.         time.sleep(0.2)
11. if __name__ == '__main__':
12.     sing_pro = multiprocessing.Process(target=sing)
13.     dance_pro = multiprocessing.Process(target=dance)
14.     sing_pro.start()
15.     dance_pro.start()

1. import multiprocessing
2. import time
3. import os
4. def sing():
5. print('sing的父进程id:',os.getppid())
6. for i in range(3):
7. print(f"唱歌第{i}次")
8.         time.sleep(1)
9.         os.kill(os.getpid(),9)
10. #       强制结束进程
11. def dance():
12. for i in range(3):
13. print(f"跳舞第{i}次")
14.         time.sleep(1)
15. if __name__ == '__main__':
16.     sing_pro = multiprocessing.Process(target=sing)
17.     dance_pro = multiprocessing.Process(target=dance)
18. print("sing:", sing_pro)
19. print("dance:", dance_pro)
20.     sing_pro.start()
21.     dance_pro.start()
22. print("main:",os.getpid(),multiprocessing.current_process())

1. import multiprocessing
2. def show(name,age):
3. print(f"姓名:{name},年龄是{age}岁")
4. if __name__ == '__main__':
5.     show_pro1=multiprocessing.Process(target=show("coleak1",19))
6.     show_pro2=multiprocessing.Process(target=show,args=('coleak2',20))
7.     show_pro3=multiprocessing.Process(target=show,kwargs={"age":21,"name":'coleak3'})
8.     show_pro1.start()
9.     show_pro2.start()
10.     show_pro3.start()

1. import multiprocessing
2. import time
3. import multiprocessing
4. my_list=list()
5. def add():
6. for i in range(3):
7.         my_list.append(i)
8. print("add:",i)
9.         time.sleep(0.5)
10. print(my_list)
11. def read():
12. print("read:",my_list)
13. if __name__ == '__main__':
14.     p1 = multiprocessing.Process(target=add)
15.     p2 = multiprocessing.Process(target=read)
16.     p1.start()
17.     p1.join()
18. #当前进程等待p1进程执行结束后再执行
19.     p2.start()
20. print("main:",my_list)

1. import multiprocessing
2. import time
3. def test():
4. for i in range(6):
5. print(i)
6.         time.sleep(0.2)
7. if __name__ == '__main__':
8.     p1=multiprocessing.Process(target=test)
9.     p1.start()
10.     time.sleep(0.5)
11. print('over!')

1. import multiprocessing
2. import time
3. def test():
4. while True:
5. print('执行ing...')
6.         time.sleep(0.2)
7. if __name__ == '__main__':
8.     p1=multiprocessing.Process(target=test)
9.     p1.daemon=True
10. # 子进程守护主进程
11.     p1.start()
12.     time.sleep(0.5)
13. print('over!')

1. import multiprocessing
2. import time
3. def test():
4. while True:
5. print('执行ing...')
6.         time.sleep(0.2)
7. if __name__ == '__main__':
8.     p1=multiprocessing.Process(target=test,name='coleak')
9.     p1.start()
10.     time.sleep(0.5)
11.     p1.terminate()
12. print('over!')

1. import threading
2. import time
3. def sing():
4. for i in range(3):
5. print(f"唱歌第{i}次")
6.         time.sleep(0.2)
7. def dance():
8. for i in range(3):
9. print(f"跳舞第{i}次")
10.         time.sleep(0.2)
11. if __name__ == '__main__':
12.     t1=threading.Thread(target=sing)
13.     t2=threading.Thread(target=dance)
14.     t1.start()
15.     t2.start()

1. import threading
2. import time
3. def test():
4.     t=threading.current_thread()
5. print('test:',t)
6. 
7. if __name__ == '__main__':
8. print("main:",threading.current_thread())
9.     t1=threading.Thread(target=test)
10.     t1.start()

1. import threading
2. import time
3. def test():
4.     time.sleep(1)
5. print(threading.current_thread())
6. if __name__ == '__main__':
7. for i in range(20):
8.         t=threading.Thread(target=test)
9.         t.start()

1. import threading
2. import time
3. def test():
4. while True:
5. print('执行ing...')
6.         time.sleep(0.2)
7. if __name__ == '__main__':
8.     p1=threading.Thread(target=test,daemon=True)
9.     p1.start()
10.     time.sleep(0.5)
11. print('over!')

1. import threading
2. import time
3. def test():
4. while True:
5. print('执行ing...')
6.         time.sleep(0.2)
7. if __name__ == '__main__':
8.     p1=threading.Thread(target=test)
9.     p1.setDaemon(True)
10.     p1.start()
11.     time.sleep(0.5)
12. print('over!')

1. import threading
2. import time
3. def test():
4. for i in range(3):
5.         my_list.append(i)
6. print("add:",i)
7. if __name__ == '__main__':
8.     my_list = list()
9.     p1=threading.Thread(target=test)
10.     p1.start()
11.     time.sleep(1)
12. print(my_list)

1. import threading
2. import time
3. a=0
4. def test1():
5. global a
6. for i in range(1000000):
7.         a+=1
8. def test2():
9. global a
10. for i in range(1000000):
11.         a+=1
12. if __name__ == '__main__':
13.     p1=threading.Thread(target=test1)
14.     p2=threading.Thread(target=test2)
15.     p1.start()
16.     p2.start()
17. print(a)

1. import threading
2. import time
3. a=0
4. lock=threading.Lock()
5. def test1():
6.     lock.acquire()
7. for i in range(1000000):
8. global a
9.         a+=1
10. # print(a)
11.     lock.release()
12. def test2():
13.     lock.acquire()
14. for i in range(1000000):
15. global a
16.         a+=1
17. # print(a)
18.     lock.release()
19. if __name__ == '__main__':
20.     p1=threading.Thread(target=test1)
21.     p2=threading.Thread(target=test2)
22.     p1.start()
23.     p2.start()
24.     time.sleep(2)
25. print(a,'over')

1. import threading
2. import time
3. lock=threading.Lock()
4. def get(index):
5.     my_list=[6,5,8,7]
6.     lock.acquire()
7. if index>=len(my_list):
8. print("下标越界",index)
9. return
10. print(my_list[index])
11.     lock.release()
12. 
13. if __name__ == '__main__':
14. for i in range(10):
15.         p=threading.Thread(target=get,args=(i,))
16.         p.start()

1. import threading
2. import time
3. lock=threading.Lock()
4. def get(index):
5.     my_list=[6,5,8,7]
6.     lock.acquire()
7. if index>=len(my_list):
8. print("下标越界",index)
9.         lock.release()
10. return
11. print(my_list[index])
12.     lock.release()
13. 
14. if __name__ == '__main__':
15. for i in range(10):
16.         p=threading.Thread(target=get,args=(i,))
17.         p.start()