System.Net.Sockets.BaseOverlappedAsyncResult.PostCompletion C# (CSharp) Метод

        internal virtual object PostCompletion(int numBytes)
        {
            _numBytes = numBytes;
            return s_resultObjectSentinel; // return sentinel rather than boxing numBytes
        }

        //
        // The overlapped function called (either by the thread pool or the socket)
        // when IO completes. (only called on Win9x)
        //
        private void OverlappedCallback(object stateObject, bool Signaled)
        {
#if DEBUG
            // GlobalLog.SetThreadSource(ThreadKinds.Worker);  Because of change 1077887, need logic to determine thread type here.
            using (GlobalLog.SetThreadKind(ThreadKinds.System)) {
#endif
            BaseOverlappedAsyncResult asyncResult = (BaseOverlappedAsyncResult)stateObject;

            GlobalLog.Assert(!asyncResult.InternalPeekCompleted, "AcceptOverlappedAsyncResult#{0}::OverlappedCallback()|asyncResult.IsCompleted", ValidationHelper.HashString(asyncResult));
            //
            // the IO completed asynchronously, see if there was a failure the Internal
            // field in the Overlapped structure will be non zero. to optimize the non
            // error case, we look at it without calling WSAGetOverlappedResult().
            //
            uint errorCode = (uint)Marshal.ReadInt32(IntPtrHelper.Add(asyncResult.m_UnmanagedBlob.DangerousGetHandle(),
                                                                      Win32.OverlappedInternalOffset));
            uint numBytes = errorCode != 0 ? unchecked ((uint)-1) : (uint)Marshal.ReadInt32(IntPtrHelper.Add(asyncResult.m_UnmanagedBlob.DangerousGetHandle(),
                                                                                                             Win32.OverlappedInternalHighOffset));
            //
            // this will release the unmanaged pin handles and unmanaged overlapped ptr
            //
            asyncResult.ErrorCode = (int)errorCode;
            object returnObject = asyncResult.PostCompletion((int)numBytes);
            asyncResult.ReleaseUnmanagedStructures();
            asyncResult.InvokeCallback(returnObject);
#if DEBUG
        }
#endif
        }