进程和线程_2

1、继承类创建线程

1 import threading,time 2  3 class Mythread(threading.Thread):       #建立类，继承threading.Thread 4     def __init__(self): 5         threading.Thread.__init__(self)     #继承父类的__init__功能 6  7     def run(self):          #run为python 自带，后面实例化后，start（）自动调用run（）功能 8         print("{name} start to read in the {time}.".format(name=self,time = time.ctime())) 9 10 l = []11 for i in range(6):12     t = Mythread()13     t.start()                       #相当于t.run() 14     l.append(t)15     t.join()16 17 # for j in l:18 #     j.join()19 20 print("All is end...{time}".format(time=time.ctime()))

 

2、互斥锁

1 import threading 2 import time 3  4 lock = threading.Lock()         #引用互斥锁，使用前先定义 5  6 def sub(): 7     global num 8     lock.acquire()              #lock.aquire() 引用锁后，只有运行到release（）才能让其它单位继续引用 9     temp = num10     time.sleep(0.1)11     num = temp - 112     lock.release()              #释放锁13     time.sleep(2)14 15 num = 10016 l = []17 for i in range(100):18     t = threading.Thread(target=sub,args=())19     t.start()20     l.append(t)21 22 for t in l:23     t.join()24 25 print(num)

 

 

3、递归锁和死锁

import threading,timeRlock = threading.RLock()  #Rlock引入Lock和counter变量，每进行一次acquire，counter计数一次，release则减少一次，直到归0，其它线程才可以获得资源。class Th(threading.Thread):    def __init__(self):        threading.Thread.__init__(self)    def run(self):        self.foo()        self.bar()    def foo(self):        Rlock.acquire()        print("I am %s GET LOCKA.....%s" %(self.name,time.ctime()))        Rlock.acquire()        print("I am %s GET LOCKB.....%s" %(self.name,time.ctime()))        Rlock.release()        Rlock.release()    def bar(self):        Rlock.acquire()        print("I am %s GET LOCKA.....%s" %(self.name,time.ctime()))        time.sleep(1)        Rlock.acquire()        print("I am %s GET LOCKB.....%s" %(self.name,time.ctime()))        Rlock.release()        Rlock.release()for i in range(10):    t = Th()    t.start()