System.Threading.ThreadPoolBoundHandle.AllocateNativeOverlapped C# (CSharp) Метод

        public unsafe NativeOverlapped* AllocateNativeOverlapped(IOCompletionCallback callback, object state, object pinData)
        {
            if (callback == null)
                throw new ArgumentNullException(nameof(callback));

            AddRef();
            try
            {
                Win32ThreadPoolNativeOverlapped* overlapped = Win32ThreadPoolNativeOverlapped.Allocate(callback, state, pinData, preAllocated: null);
                overlapped->Data._boundHandle = this;

                Interop.Kernel32.StartThreadpoolIo(_threadPoolHandle);

                return Win32ThreadPoolNativeOverlapped.ToNativeOverlapped(overlapped);
            }
            catch
            {
                Release();
                throw;
            }
        }

 private Interop.HttpApi.HTTP_REQUEST* Allocate(ThreadPoolBoundHandle boundHandle, uint size)
 {
     uint newSize = size != 0 ? size : RequestBuffer == null ? 4096 : Size;
     if (_nativeOverlapped != null && newSize != RequestBuffer.Length)
     {
         NativeOverlapped* nativeOverlapped = _nativeOverlapped;
         _nativeOverlapped = null;
         _boundHandle.FreeNativeOverlapped(nativeOverlapped);
     }
     if (_nativeOverlapped == null)
     {
         SetBuffer(checked((int)newSize));
         _boundHandle = boundHandle;
         _nativeOverlapped = boundHandle.AllocateNativeOverlapped(ListenerAsyncResult.IOCallback, state: _result, pinData: RequestBuffer);
         return (Interop.HttpApi.HTTP_REQUEST*)Marshal.UnsafeAddrOfPinnedArrayElement(RequestBuffer, 0);
     }
     return RequestBlob;
 }