cannot convert '*void(MyClass::*)(void*) to void*(*)(void*) in pthread_create function

Question

i\'m trying to create a new thread with a class \"CameraManager\" but i have the following error:

cannot convert \'*void(CameraManager:: * )(void*) to

Answer 1

If you want the function to be a member of the class, it must be static. It's because the thread function will be called directly and will not have a valid this pointer. This can be solved by having a wrapper function, that gets passed the actual object and then calls the proper member function:

void *dequeueLoopWrapper(void *p)
{
    CameraManager *cameraManager = static_cast(p);
    camereraManager->dequeueLoop();
    return nullptr;
}

// ...

void CameraManager::startDequeuing()
{
    dequeuing = true;
    dequeueThreadId = pthread_create(&dequeueThread, NULL, dequeueLoopWrapper, this);
}

However, I would recommend you start using the threading support in the new standard library:

void CameraManager::startDequeuing()
{
    dequeuing = true;
    myThread = std::thread(&CameraManager::dequeueLoop, this);
}