FilesExpand file tree

 master

/

p_lock.py

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

34 lines (31 loc) · 797 Bytes

 master

/

p_lock.py

Copy path

Top

File metadata and controls

• Code
• Blame

34 lines (31 loc) · 797 Bytes

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

import threading

import time

# globals_num = 0

#

# lock = threading.RLock()

#

# def f():

# lock.acquire()

# global globals_num

# globals_num += 1

# time.sleep(0.5)

# print(globals_num)

# lock.release()

#

# for i in range(10):

# t = threading.Thread(target=f)

# t.start()

'''

RLock允许在同一线程中被多次acquire。而Lock却不允许这种情况。

如果使用RLock，那么acquire和release必须成对出现，即调用了n次acquire，必须调用n次的release才能真正释放所占用的琐。

'''

# lock = threading.Lock()

# lock.acquire()

# lock.acquire() # 产生了死琐

# lock.release()

# lock.release()

lock = threading.RLock()

lock.acquire()

lock.acquire() # 在同一线程内，程序不会堵塞

lock.release()

lock.release()