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

libc: Make various internal file descriptors from fopen() close-on-exec.

Fix struct FILE * leak on error (in disabled by default hesiod support code).

Submitted by: henning petersen <henning.petersen t-online de>
PR: 153756
MFC after: 1 week

Back out the `hiding' of strlcpy and strlcat. Several people
vocally objected to this safety belt.

`Hide' strlcpy and strlcat (using the namespace.h / __weak_reference
technique) so that we don't wind up calling into an application's
version if the application defines them.

Inspired by: qpopper's interfering and buggy version of strlcpy

Check for truncation in calls to res_send/res_query/res_search.
Fail when it is detected.

Fix the style of the SCM ID's.
I believe have made all of libc .c's as consistent as possible.

Remove __P() usage.

strcpy -> strlcpy paranoia

Submitted by: Mike Heffner <mheffner@vt.edu>
Reviewed by: freebsd-audit

Use issetugid instead of comparing get[ug]id and gete[ug]id.

Suggested by: Don Lewis <Don.Lewis@tsc.tdk.com>

Ignore HESIOD_CONFIG and HES_DOMAIN environmental variables for
set-user-ID and set-group-ID programs.

Suggested by: Danny Braniss <danny@cs.huji.ac.il>

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