System.IO.FileStream.LockInternal C# (CSharp) Method

        private void LockInternal(long position, long length)
        {
            int positionLow = unchecked((int)(position));
            int positionHigh = unchecked((int)(position >> 32));
            int lengthLow = unchecked((int)(length));
            int lengthHigh = unchecked((int)(length >> 32));

            if (!Interop.Kernel32.LockFile(_fileHandle, positionLow, positionHigh, lengthLow, lengthHigh))
            {
                throw Win32Marshal.GetExceptionForLastWin32Error();
            }
        }