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其实可以不需要使用lock

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梦想家高先森

#1 Created at ... [Delete] [Delete and Lock User]

把例子中的

t1.start()
t2.start()
t1.join()
t2.join()

修改为

t1.start()
t1.join()
t2.start()
t2.join()

如此，便可以不需要使用低级的lock()，也能得到正确的结果。

阿狸不在q

#2 Created at ... [Delete] [Delete and Lock User]

你这样不就失去了多线程的意义了吗，一个一个跑的话还要写多线程干嘛

梦想家高先森

#3 Created at ... [Delete] [Delete and Lock User]

但lock这种操作其实就是把并行强行改为串行，我想要表达的意思是，这种方法通过join做中介其实也可以实现

为了不泄漏隐私

#4 Created at ... [Delete] [Delete and Lock User]

lock只是锁住了修改参数的过程而已，你这里确实是直接把程序变成串行的了。 你这样做，对于这个问题确实可以实现相同的操作，因为他确实只有一个步骤（甚至不算for...range 那里）。但是在别的地方就不能这么用了。一个线程可以有很多步骤的，lock只是锁了其中一个步骤而已。

风萧萧兮_63711

#5 Created at ... [Delete] [Delete and Lock User]

它只是保持每次只有一个线程操作参数，但是不代表每个线程的操作是顺序的，下面这程序多运行几次会发现它并不是线性运行的，它是由系统分配运行的

import threading
import time, random

class myThread (threading.Thread):
    def __init__(self, threadID, name):
        threading.Thread.__init__(self)
        self.threadID = threadID
        self.name = name

    def run(self):
        print ("开启线程： " + self.name)
        #获取锁，用于线程同步
        threadLock.acquire()
        print_time(self.name, 4)
        # 释放锁，开启下一个线程
        threadLock.release()

def print_time(threadName, counter):
    while counter:
        time.sleep(0.4)
        #打印时间
        print ("%s: %s" % (threadName, time.ctime(time.time())))
        counter -= 1

threadLock = threading.Lock()
threads = []
th_name = ["Thread-1","Thread-2","Thread-3","Thread-4"]
# 创建新线程
for i, n in zip(range(1,5),th_name):
    t = myThread(i, n)
    t.start()
    threads.append(t)
    #t.join()
# 开启新线程
for t in threads:
    t.join()

~
执行结果： 开启线程： Thread-1 开启线程： Thread-2 开启线程： Thread-4 开启线程： Thread-3 Thread-1: Sat May 12 01:38:57 2018 Thread-1: Sat May 12 01:38:57 2018 Thread-1: Sat May 12 01:38:58 2018 Thread-1: Sat May 12 01:38:58 2018 Thread-2: Sat May 12 01:38:59 2018 Thread-2: Sat May 12 01:38:59 2018 Thread-2: Sat May 12 01:38:59 2018 Thread-2: Sat May 12 01:39:00 2018 Thread-4: Sat May 12 01:39:00 2018 Thread-4: Sat May 12 01:39:01 2018 Thread-4: Sat May 12 01:39:01 2018 Thread-4: Sat May 12 01:39:01 2018 Thread-3: Sat May 12 01:39:02 2018 Thread-3: Sat May 12 01:39:02 2018 Thread-3: Sat May 12 01:39:03 2018 Thread-3: Sat May 12 01:39:03 2018

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