HP-UX IPv6 Porting Guide (February 2007)

IPv6 Addressing

IPv6 Address Types

Chapter 212

NOTE Only use the constant during initialization.

• For assignment, use the global variable named in6addr_any, of the type in6_addr

structure. For example:

Header file

extern const struct in6_addr in6addr_any;

struct sockaddr_in6 sin6;

…

sin6.sin6_addr = in6addr_any; /* structure assignment */

…

if (bind(s, (struct sockaddr *) &sin6, sizeof(sin6)) == -1)

IPv6 Loopback Addresses

The IPv4 loopback address is an integer type INADDR_LOOPBACK. The IPv6 loopback address is

an in6_addr structure defined in <netinet/in.h>. For example:

Header file

sin6.sin6_addr = in6addr_loopback; /* structure assignment */

The symbolic constant named IN6ADDR_LOOPBACK_INIT is defined in <netinet/in.h>. Use it

only when declaring a sockaddr_in6 struct. For example:

struct in6_addr loopbackaddr = IN6ADDR_LOOPBACK_INIT

NOTE IPv4 defines INADDR_* constants in IPv4 host byte order. However, IPv6

defines IN6ADDR_* and in6addr* constants in network byte order.