python 线程锁

保护数据安全性：

lock = threading.RLock()


def Func():
    lock.acquire()
    #局部变量默认不能修改全局变量
    global gl_num
    gl_num += 1
    time.sleep(1)
    print(gl_num)
    lock.release()


for i in range(10):
    t = threading.Thread(target=Func)
    t.start()

同时分配锁给多个线程：

#！/usr/bin/python
#_*_ coding:UTF-8 _*_

import threading
import time

gl_num = 0

bsm = threading.BoundedSemaphore(4)


def Func():
    bsm.acquire()
    #局部变量默认不能修改全局变量
    global gl_num
    gl_num += 1
    time.sleep(1)
    print(gl_num)
    bsm.release()


for i in range(10):
    t = threading.Thread(target=Func)
    t.start()

执行结果：

4
5
6
7
8
8
10
10
10
10