HRESULT XGameGetXboxTitleId(  
         uint32_t* titleId  
)  

std::string GetBackendServiceUrl()  
{  
    uint32_t titleId;  
  
    RetailAssert(SUCCEEDED(XGameGetXboxTitleId(&titleId)));  
  
    std::stringstream url;  
    url << "https://example.com/some/api/call";  
  
    url << std::hex << std::uppercase << std::setfill('0');  
    url << "/titleId/" << std::setw(8) << titleId;  
  
    return url.str();  
}