IPAddr.ntop

# File tmp/rubies/ruby-4.0.0/lib/ipaddr.rb, line 115
def self.ntop(addr)
  if addr.is_a?(String) && addr.encoding != Encoding::BINARY
    raise InvalidAddressError, "invalid encoding (given #{addr.encoding}, expected BINARY)"
  end

  case addr.bytesize
  when 4
    addr.unpack('C4').join('.')
  when 16
    IN6FORMAT % addr.unpack('n8')
  else
    raise AddressFamilyError, "unsupported address family"
  end
end