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 = num
10 time.sleep(0.1)
11 num = temp - 1
12 lock.release() #释放锁
13 time.sleep(2)
14
15 num = 100
16 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,time
Rlock = 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()
