NetBSD 5.0’s lacks AI_* macros

[Ludovic Courtès]

Hello,

NetBSD 5.0’s <netdb.h> doesn’t define ‘AI_ALL’, ‘AI_V4MAPPED’, and
‘AI_ADDRCONFIG’.  This can be worked around with something like this:

  #ifndef AI_ALL
  # define AI_ALL 0
  #endif
  #ifndef AI_V4MAPPED
  # define AI_V4MAPPED 0
  #endif
  #ifndef AI_ADDRCONFIG
  # define AI_ADDRCONFIG 0
  #endif

Thanks,
Ludo’.