How to: Using the process task queue

Example

The default process task queue uses the thread pool for both work and completion dispatching. Microsoft Game Development Kit (GDK) APIs that take task queue parameters all accept nullptr and substitute the process task queue. It can be replaced. The process task queue can also be set to nullptr. In this case, Microsoft Game Development Kit (GDK) APIs that require a task queue parameter will error with E_NO_TASK_QUEUE. This allows the Microsoft Game Development Kit (GDK) APIs to function with defaults while still allowing tight control over task queue handles, if needed.

The following example shows how to use the process task queue.

void UsingProcessTaskQueue()  
{  
    XTaskQueueHandle queue = GetCurrentProcessTaskQueue();  
  
    auto callback = [](void*, bool)  
    {  
        printf("Work callback invoked.\r\n");  
    };  
  
    HRESULT hr = XTaskQueueSubmitCallback(  
        queue, XTaskQueuePort::Work,  
        nullptr, callback);  
  
    if (FAILED(hr))  
    {  
        printf("Failed to submit callback: %x\r\n", hr);  
        return;  
    }  
  
    // You can replace the process task queue.  
    hr = XTaskQueueCreate(  
        XTaskQueueDispatchMode::Manual,  
        XTaskQueueDispatchMode::Manual,  
        &queue);  
  
    if (FAILED(hr))  
    {  
        printf("Failed to create new task queue: %x\r\n", hr);  
        return;  
    }  
  
    XTaskQueueSetCurrentProcessTaskQueue(queue);  
  
    XTaskQueueHandle processQueue;  
    XTaskQueueGetCurrentProcessTaskQueue(&processQueue);  
    printf("Process task queue: %p. Our queue: %p\r\n",  
        processQueue, queue);  
    XTaskQueueCloseHandle(processQueue);  
  
    // You can set the process queue to nullptr to force everyone to pass a queue  
    // as a parameter.  
    XTaskQueueSetCurrentProcessTaskQueue(nullptr);  
    XTaskQueueGetCurrentProcessTaskQueue(&processQueue);  
    printf("Process task queue: %p.\r\n",  
        processQueue);  
}  

See also

Designing the task queue