Boost message_queue: when I receive an object, how can I remove it from the queue? [closed]

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I noticed that, when I get an object from a Boost message_queue with the *receive() member functions, that object remains in the queue. So if I read the same message_queue multiple times, I keep getting copies of the same objects, even if nothing has been inserted from the other side.

Is there a way to remove an object from the queue once it has been read?

E.g.:

boost::scoped_ptr<boost::interprocess::message_queue> pMQueue;

message_queue::remove("myQueue");

pMQueue.reset(new message_queue(open_or_create, "myQueue", 100, sizeof(MyClass)));

MyClass token;
std::vector<MyClass> tokens;
size_t recvdSize = 0;
float timeDelay = 100;  // milliseconds
bool dataAvailable = true;

// If I do this block twice, I receive the same tokens twice

while(dataAvailable)
{
    ptime t = microsec_clock::universal_time() + milliseconds(timeDelay);

    dataAvailable = pMQueue->timed_receive(&token, sizeof(token), recvdSize, 0, t);

    if(dataAvailable && recvdSize > 0)
        tokens.push_back(token);
    else if(recvdSize == 0)
   开发者_开发百科     break;
    else if(recvdSize != sizeof(token))
        exit(1);
}

---

Ops, I found a bug in my code. The message_queue works as expected, the problem was in the way the tokens container was managed.