Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Consistently use 'af' as an argument name for address family.
Now both gethostbyname2(3) and gethostbyaddr(3) use the same argument name.
The same argument name is also used in implementations of those functions.

Per Regents of the University of Calfornia letter, remove advertising
clause.

# If I've done so improperly on a file, please let me know.

Document return values for res_query and res_search.
h_errno is not an extern int, just a macro providing an integer lvalue.

PR: doc/50573
Submitted by: Ronald F.Guilmette <rfg@monkeys.com>
Reviewed by: trhodes
MFC after: 3 days

Markup fixes.

Fix gethostbyaddr() prototype to conform to IEEE Std 1003.1:

http://www.opengroup.org/onlinepubs/009695399/functions/gethostbyaddr.html

gethostbyaddr_r() is changed as well.
It breaks ABI backward compatibility on 64 bit arch. So, we fix it
on 32 bit arch only for now.

Reported by: Rostislav Krasny <rosti.bsd@gmail.com>

make gethostby*() thread-safe.

add IPv6 awareness for NIS query of gethostby*().

Inspired by: NetBSD

Mechanically kill hard sentence breaks.

Make the resolver(3) and many associated interfaces much more reentrant.
The getaddrinfo(3), getipnodebyname(3) and resolver(3) can coincide now
with what should be totally reentrant, and h_errno values will now
be preserved correctly, but this does not affect interfaces such as
gethostbyname(3) which are still mostly non-reentrant.

In all of these relevant functions, the thread-safety has been pushed
down as far as it seems possible right now. This means that operations
that are selected via nsdispatch(3) (i.e. files, yp, dns) are protected
still under global locks that getaddrinfo(3) defines, but where possible
the locking is greatly reduced. The most noticeable improvement is
that multiple DNS lookups can now be run at the same time, and this
shows major improvement in performance of DNS-lookup threaded programs,
and solves the "Mozilla tab serialization" problem.

No single-threaded applications need to be recompiled. Multi-threaded
applications that reference "_res" to change resolver(3) options will
need to be recompiled, and ones which reference "h_errno" will also
if they desire the correct h_errno values. If the applications already
understood that _res and h_errno were not thread-safe and had their own
locking, they will see no performance improvement but will not
actually break in any way.

Please note that when NSS modules are used, or when nsdispatch(3)
defaults to adding any lookups of its own to the individual libc
_nsdispatch() calls, those MUST be reentrant as well.

.Xr -> .Lb for librairy. There is no manual page corresponding to .Xr.

The .Fn function

mdoc(7) police: "The .Fa argument.".

mdoc(7) police: "The .Fn function".

yp(4) -> yp(8).

PR: docs/30797

mdoc(7) police: Use the new .In macro for #include statements.

Urge the reader to start using getaddrinfo(3) and getnameinfo(3)
protocol-independant functions that don't use static memory area.

Suggested by: nik
Liked by: ume, brian

Remove whitespace at EOL.

mdoc(7) police: removed HISTORY info from the .Os call.

mdoc(7) police: sort xrefs.

gethostbyname2() can't do AF_INET6 lookups over NIS.
getaddrinfo(3) must be used.

Submitted by: ume

Add getaddrinfo(3) to the "SEE ALSO" list.

mdoc(7) police: polishing.

Describe the arguments to gethostbyaddr.

PR: docs/24225
Submitted by: Joakim Henriksson <jurduth@ludd.luth.se>
Patch from: ben

mdoc(7) police: Ft/Vt now accept punctuation-type arguments.

gethostbyname2() is able to lookup AF_INET6.

PR: 23823
Noticed by: Andrew Arensburger <arensb@ooblick.com>

Add nsswitch support. By creating an /etc/nsswitch.conf file, you can
configure FreeBSD so that various databases such as passwd and group can be
looked up using flat files, NIS, or Hesiod.

= Hesiod has been added to libc (see hesiod(3)).

= A library routine for parsing nsswitch.conf and invoking callback
functions as specified has been added to libc (see nsdispatch(3)).

= The following C library functions have been modified to use nsdispatch:
. getgrent, getgrnam, getgrgid
. getpwent, getpwnam, getpwuid
. getusershell
. getaddrinfo
. gethostbyname, gethostbyname2, gethostbyaddr
. getnetbyname, getnetbyaddr
. getipnodebyname, getipnodebyaddr, getnodebyname, getnodebyaddr

= host.conf has been removed from src/etc. rc.network has been modified
to warn that host.conf is no longer used at boot time. In addition, if
there is a host.conf but no nsswitch.conf, the latter is created at boot
time from the former.

Obtained from: NetBSD

Introduce ".Lb" macro to libc manpages.

More libraries manpages updates following.

Fix typo

PR: docs/13814
Submitted by: Alex Vasylenko <lxv@mix.nest.org>

$Id$ -> $FreeBSD$

Spelling corrections.

PR: 6868
Submitted by: Josh Gilliam <josh@quick.net>

(Ab)use .Vt instead of .Fd for a variable declaration.

Typo.

Fixed missing function types in synopsis.

Doc updates and cleanups made with the bind-4.9.4 update some time ago.
I thought I had committed these, but it seems not.

Fix an error in the description of "h_errno". Add "const" to a few
declarations to make them agree with the actual prototypes in <netdb.h>.

back out last two changes, this caused the mandoc pages to be replaced by
man pages. I'll fold in the real changes in a seperate commit.

The last commit failed part-way through, re-add the generated
resolver man pages.