Qt的QWaitCondition（允许线程在一定条件下唤醒其他线程，这样对不间断上传可能比较适用）

#include <QtCore/QCoreApplication>
#include <QWaitCondition>
#include <QThread>
#include <QMutex>
#include <iostream>

const int DataSize = 100;
const int BufferSize = 1;
char buffer[BufferSize];

QWaitCondition bufferIsNotFull;
QWaitCondition bufferIsNotEmpty;
QMutex mutex;
int usedSpace;

class Producer : public QThread
{
protected:
    void run()
    {
        for (int i = 0; i < DataSize; ++i)
        {
            mutex.lock();
            while (usedSpace == BufferSize)
            {
                bufferIsNotFull.wait(&mutex);
            }
            std::cerr<<"P";
            ++usedSpace;
            bufferIsNotEmpty.wakeAll();
            mutex.unlock();
        }
    }
};

class Consumer : public QThread
{
protected:
    void run()
    {
        for (int i = 0; i < DataSize; ++i)
        {
            mutex.lock();
            while (usedSpace == 0)
            {
                bufferIsNotEmpty.wait(&mutex);
            }
            std::cerr<<"C";
            --usedSpace;
            bufferIsNotFull.wakeAll();
            mutex.unlock();
        }
        std::cerr<<std::endl;
    }
};

int main(int argc, char *argv[])
{
   Producer producer;
   Consumer consumer;
   producer.start();
   consumer.start();
   producer.wait();
   consumer.wait();
return 0;
}