[krbdev.mit.edu #3421] HPUX 11.22 getaddrinfo() issues

[Ken Raeburn via RT]

> - Despite being given both a host and service name, getaddrinfo() on
> HPUX 11.22 sometimes returns EAI_NONAME.  To fix, the patch adds a check
> for gethostbyname and getservbyname and falls back on them in the case
> of HPUX and a return of EAI_NONAME.

Rather than make lots of different bits of code work with both
getaddrinfo and gethostbyname, we've implemented a wrapper around the
getaddrinfo interface which patches up bogus results (e.g., sa_len field
unset on AIX) and implements the functionality if the OS doesn't provide
getaddrinfo at all (old IRIX systems we've still got lying around here).
 That would be the right place to fix this, I think, rather than just in
the telnet client program.  (If it breaks for telnet, why not for the
library attempting to contact the KDC?)

Also, is this random flakiness, or is it a consistent problem caused by
incorrect configuration (e.g., if getaddrinfo uses different config
data, like a different nsswitch entry, from gethostbyname)?