On Tue, Jun 14, 2011 at 04:38:06PM +0700, Fajar A. Nugraha <work at fajar.net> wrote a message of 29 lines which said: > most programming language has gethostbyname() and gethostbyaddr() These routines are deprecated for a long time (the main reason being they are specific of an old version of IP) and you should use getaddrinfo() and getnameinfo() instead.