inet_pton inet_ntop roll your own

Question

Our code has to run on both SLES9 (old) and an even older version HPUX. We're implementing IPv6 now, but inet_pton and inet_ntop do not exist on our HPUX, so have to roll our own.

S/W is in C++. If I have an IPv6 address string, can someone provide the C/C++ equivalent of the above 2 methods?

Many Thanks!