I stumbled upon this post recently and think that it needs an updated solution for the standard library's c++11 mutex (namely std::mutex).
I've pasted some code below (my first steps with a mutex - I learned concurrency on win32 with HANDLE, SetEvent, WaitForMultipleObjects etc).
Since it's my first attempt with std::mutex and friends, I'd love to see comments, suggestions and improvements!
#include <condition_variable>
#include <mutex>
#include <algorithm>
#include <thread>
#include <queue>
#include <chrono>
#include <iostream>
int _tmain(int argc, _TCHAR* argv[])
{
// these vars are shared among the following threads
std::queue<unsigned int> nNumbers;
std::mutex mtxQueue;
std::condition_variable cvQueue;
bool m_bQueueLocked = false;
std::mutex mtxQuit;
std::condition_variable cvQuit;
bool m_bQuit = false;
std::thread thrQuit(
[&]()
{
using namespace std;
this_thread::sleep_for(chrono::seconds(5));
// set event by setting the bool variable to true
// then notifying via the condition variable
m_bQuit = true;
cvQuit.notify_all();
}
);
std::thread thrProducer(
[&]()
{
using namespace std;
int nNum = 13;
unique_lock<mutex> lock( mtxQuit );
while ( ! m_bQuit )
{
while( cvQuit.wait_for( lock, chrono::milliseconds(75) ) == cv_status::timeout )
{
nNum = nNum + 13 / 2;
unique_lock<mutex> qLock(mtxQueue);
cout << "Produced: " << nNum << "\n";
nNumbers.push( nNum );
}
}
}
);
std::thread thrConsumer(
[&]()
{
using namespace std;
unique_lock<mutex> lock(mtxQuit);
while( cvQuit.wait_for(lock, chrono::milliseconds(150)) == cv_status::timeout )
{
unique_lock<mutex> qLock(mtxQueue);
if( nNumbers.size() > 0 )
{
cout << "Consumed: " << nNumbers.front() << "\n";
nNumbers.pop();
}
}
}
);
thrQuit.join();
thrProducer.join();
thrConsumer.join();
return 0;
}