System.Net.Sockets.SocketAsyncEventArgs.PinSocketAddressBuffer C# (CSharp) Method

        private void PinSocketAddressBuffer()
        {
            // Check if already pinned.
            if (_pinnedSocketAddress == _socketAddress)
            {
                return;
            }

            // Unpin any existing.
            if (_socketAddressGCHandle.IsAllocated)
            {
                _socketAddressGCHandle.Free();
            }

            // Pin down the new one.
            _socketAddressGCHandle = GCHandle.Alloc(_socketAddress.Buffer, GCHandleType.Pinned);
            _socketAddress.CopyAddressSizeIntoBuffer();
            _ptrSocketAddressBuffer = Marshal.UnsafeAddrOfPinnedArrayElement(_socketAddress.Buffer, 0);
            _ptrSocketAddressBufferSize = Marshal.UnsafeAddrOfPinnedArrayElement(_socketAddress.Buffer, _socketAddress.GetAddressSizeOffset());
            _pinnedSocketAddress = _socketAddress;
        }