Portability (2)

If you want your software be usable on platforms without getaddrinfo/getnameinfo?

Use GNU autoconf
Include minimal implementation of getaddrinfo/getnameinfo into distribution
AC_REPLACE_FUNCS() will include *.o when the functions are missing

AC_CHECK_LIB(getaddrinfo, inet6)
AC_CHECK_FUNCS(getaddrinfo)

AC_REPLACE_FUNCS(getaddrinfo getnameinfo)