class BinData::Stringz

def trim_to!(str, max_length = nil)
  if max_length
    max_length = 1 if max_length < 1
    str.slice!(max_length..-1)
    if str.length == max_length && str[-1, 1] != "\0"
      str[-1, 1] = "\0"
    end
  end
end