线程锁

from threading import Lock,Thread
import time

def func():
    global n
    temp = n
    time.sleep(0.2)
    n = temp -1
n = 10
t_lst = []
for i in range(10):
    t = Thread(target=func)
    t.start()
    t_lst.append(t)
for t in t_lst: t.join()
print(n)

 

from threading import Lock,Thread
import time

def func(lock):
    global n
    lock.acquire()
    temp = n
    time.sleep(0.2)
    n = temp -1
    lock.release()

n = 10
t_lst = []
lock = Lock()

for i in range(10):
    t = Thread(target=func,args=(lock,))
    t.start()
    t_lst.append(t)
for t in t_lst: t.join()
print(n)

 

from threading import Thread,Lock
import time

noodle_lock = Lock()
fork_lock = Lock()

def eat1(name):
    noodle_lock.acquire()
    print('%s拿到面条啦'%name)
    fork_lock.acquire()
    print('%s拿到叉子了'%name)
    print('%s吃面'%name)
    fork_lock.release()
    noodle_lock.release()

def eat2(name):
    fork_lock.acquire()
    print('%s拿到叉子了'%name)
    time.sleep(1)
    noodle_lock.acquire()
    print('%s拿到面条啦'%name)
    print('%s吃面'%name)
    noodle_lock.release()
    fork_lock.release()

Thread(target=eat1,args=('alex',)).start()
Thread(target=eat2,args=('Egon',)).start()
Thread(target=eat1,args=('bossjin',)).start()
Thread(target=eat1,args=('nezha',)).start()

 

from threading import RLock   # 递归锁
fork_lock = noodle_lock  = RLock()   # 一个钥匙串上的两把钥匙
def eat1(name):
    noodle_lock.acquire()            # 一把钥匙
    print('%s拿到面条啦'%name)
    fork_lock.acquire()
    print('%s拿到叉子了'%name)
    print('%s吃面'%name)
    fork_lock.release()
    noodle_lock.release()

def eat2(name):
    fork_lock.acquire()
    print('%s拿到叉子了'%name)
    time.sleep(1)
    noodle_lock.acquire()
    print('%s拿到面条啦'%name)
    print('%s吃面'%name)
    noodle_lock.release()
    fork_lock.release()

Thread(target=eat1,args=('alex',)).start()
Thread(target=eat2,args=('Egon',)).start()
Thread(target=eat1,args=('bossjin',)).start()
Thread(target=eat2,args=('nezha',)).start()