threadpool怎么读写全局变量？

luffy.deng

给段代码看看吧

luffy.deng

全局变量的话好像加global就行了

luffy.deng

为何不能直接用？有啥问题？

luffy.deng

好像不是那样写
import threading
share=1
def threadcode():
    global share
    share+=2
    print "childthread output",share
t = threading.Thread(target = threadcode,name='childthread')
t.setDaemon(1)
t.start()
t.join()

luffy.deng

if __name__ == '__main__':
    import random
    import time
    from threadpool import *


    # the work the threads will have to do (rather trivial in our example)
    def do_something(data):
        time.sleep(random.randint(1,5))
        result = round(random.random() * data, 5)
        print(result)
        # just to show off, we throw an exception once in a while
        #if result > 3:
            #raise RuntimeError("Something extraordinary happened!")
        return result

    # this will be called each time a result is available
    def print_result(request, result):
        global res
        res+=result
        print "**Result: %s from request #%s" % (result, request.requestID)
        
    # this will be called when an exception occurs within a thread
    def handle_exception(request, exc_info):
        print "Exception occured in request #%s: %s" % \
          (request.requestID, exc_info[1])

    # assemble the arguments for each job to a list...
    data = [random.randint(1,10) for i in range(2)]

    # ... and build a WorkRequest object for each item in data
    requests = makeRequests(do_something, data, print_result, handle_exception,)

    # or the other form of args_lists accepted by makeRequests: ((,), {})
    """
    data = [((random.randint(1,10),), {}) for i in range(20)]
    requests.extend(
      makeRequests(do_something, data, print_result, handle_exception)
    )
    """
    # we create a pool of 3 worker threads
    main = ThreadPool(3)

    res=0
    # then we put the work requests in the queue...
    for req in requests:
        main.putRequest(req)
        #print "Work request #%s added." % req.requestID
        sfd=str(req.callable)
        if sfd.find('do_something') > 0:
            print "nihao"
    # or shorter:
    # [main.putRequest(req) for req in requests]

    # ...and wait for the results to arrive in the result queue
    # by using ThreadPool.wait(). This would block until results for
    # all work requests have arrived:
    # main.wait()

    # instead we can poll for results while doing something else:
    main.wait()
    print(res)
    """
    i = 0
    while 1:
        try:
            main.poll()
            print "Main thread working..."
            time.sleep(0.5)
            if i == 10:
                print "Adding 3 more worker threads..."
                main.createWorkers(3)
            i += 1
        except KeyboardInterrupt:
            print "Interrupted!"
            break
        except NoResultsPending:
            print "All results collected."
            break
    """

luffy.deng

下面是输出，对不对？
nihao
nihao
8.34617
**Result: 8.34617 from request #57364272
0.88989
**Result: 0.88989 from request #57301352
9.23606

luffy.deng

那个库没有同步机制？那还不如自己写算了

luffy.deng

全局变量加锁应该可以。