python线程

 1 import threading
 2 from time import sleep
 3 import os
 4 
 5 a = 1
 6 
 7 # 线程函数
 8 def music():
 9     global a
10     print("a = ",a)
11     a = 10000
12     for i in range(3):
13         sleep(2)
14         print(os.getpid(),"播放: 葫芦娃")
15 
16 # 线程对象
17 t = threading.Thread(target = music)
18 t.start() # 启动线程
19 
20 for i in range(4):
21     sleep(1)
22     print(os.getpid(),"播放: 黄河大合唱")
23 
24 t.join() # 回收线程
25 
26 print("===========================")
27 
28 print("a:",a)

 1 from threading import Thread
 2 from time import sleep
 3 
 4 # 含有参数的线程函数
 5 def fun(sec,name):
 6     print("线程函数传参")
 7     sleep(sec)
 8     print("%s执行完毕"%name)
 9 
10 # 创建多个线程
11 jobs=[]
12 for i in range(3):
13     t = Thread(target=fun,args=(2,),
14                kwargs={‘name‘:‘T%d‘%i})
15     jobs.append(t)  # 存线程对象
16     t.start()
17 
18 for i in jobs:
19     i.join()

 1 from threading import Thread
 2 from time import sleep,ctime
 3 
 4 class MyThread(Thread):
 5     # __init__可以添加参数，进行编写
 6     def __init__(self,target,args=(),kwargs={}):
 7         super().__init__() # 此处不许传参
 8         self.target = target
 9         self.args = args
10         self.kwargs = kwargs
11 
12     # 添加其他方法 run
13     def run(self):
14         self.target(*self.args,**self.kwargs)
15 
16 ###########################################
17 def player(sec,song):
18     for i in range(3):
19         print("Playing %s:%s"%(song,ctime()))
20         sleep(sec)
21 
22 t = MyThread(target=player,args=(3,),
23              kwargs={‘song‘:‘凉凉‘})
24 
25 t.start()
26 t.join()

from threading import Thread,Event

s = None  # 全局变量用于通信
e = Event() # 事件对象

def 杨子荣():
    print("杨子荣前来拜山头")
    global s
    s = "天王盖地虎"
    e.set() # 修改完s

t = Thread(target=杨子荣)
t.start()

print("说对口令就是自己人")
e.wait() #阻塞等待
if s == "天王盖地虎":
    print("宝塔镇河妖")
    print("确认过眼神，你是对的人")
else:
    print("打死他!!")

t.join()

 1 from threading import Thread,Lock
 2 
 3 a = b = 0
 4 lock = Lock() # 锁对象
 5 
 6 def value():
 7     while True:
 8         lock.acquire()
 9         if a != b:
10             print(‘a = %d,b = %d‘%(a,b))
11         lock.release() # 解锁操作
12 
13 t = Thread(target=value)
14 t.start()
15 
16 while True:
17     with lock:  # with上锁
18         a += 1
19         b += 1
20                 # 语句块结束解锁
21 t.join()

 1 from time import sleep
 2 from threading import Thread,Lock
 3 
 4 # 交易类
 5 class Account:
 6     def __init__(self,_id,balance,lock):
 7         self.id = _id  # 谁
 8         self.balance = balance # 有多少钱
 9         self.lock = lock # 锁
10 
11     # 取钱
12     def withdraw(self,amount):
13         self.balance -= amount # 取多少
14 
15     # 存钱
16     def deposit(self,amount):
17         self.balance += amount # 存多少
18 
19     # 查看余额
20     def get_balance(self):
21         return self.balance
22 
23 # 创建两个账户
24 Tom = Account(‘Tom‘,5000,Lock())
25 Alex = Account(‘Alex‘,8000,Lock())
26 
27 # 转账行为
28 def transfer(from_,to,amount):
29     # 从 from_ --> to  转amount
30     if from_.lock.acquire(): # 锁住自己账户
31         from_.withdraw(amount) # 自己账户扣除
32         sleep(0.5)
33         if to.lock.acquire(): # 对方账户上锁
34             to.deposit(amount) # 对方账户增加
35             to.lock.release() # 对方解锁
36         from_.lock.release() # 自己解锁
37     print("%s给%s转了%d"%(from_.id,to.id,amount))
38 
39 t1 = Thread(target=transfer,args=(Tom,Alex,2000))
40 t2 = Thread(target=transfer,args=(Alex,Tom,3500))
41 
42 t1.start()
43 t2.start()
44 
45 t1.join()
46 t2.join()
47 
48 print(Tom.get_balance())
49 print(Alex.get_balance())