/// <summary>
/// Reads an 8-byte signed integer from the current stream and advances the current
/// position of the stream by eight bytes.
/// </summary>
/// <returns>An 8-byte signed integer read from the current stream.</returns>
public long ReadInt64()
{
Debug.Assert(_buffer != null);
var valRead = _buffer.GetLong(_offset);
_offset += WoffBuffer.SizeOfLong;
return(valRead);
}