Expect surprises with octal and hexadecimal parts:

  $ ping 10.010.23.023
  PING 10.010.23.023 (10.8.23.19) 56(84) bytes of data.
[download]

See also:

• inet_pton
• Ping and FTP Resolve IP Address with Leading Zero as Octal (Q115388)

-- Ruud