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

- sl_find does not modify 'name'
- make the prototype of sl_find match NetBSD

Reviewed by: jilles
Approved by: cperciva (mentor)
MFC After: 3 days

Switch from K&R prototypes to modern C

Reviewed by: jilles
Approved by: cperciva (mentor)
MFC After: 3 days

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

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

Sync with NetBSD -- sl_add() now returns an int.

#include "namespace.h" to get a prototype for _err().

Fix SCM ID's.

Fixed namespace pollution related to `err' in libc in the same way as for
`warn'. Now a whole 2 members of the err() family don't cause pollution.

This fixes world breakage in awk for NOSHARED worlds. contrib/awk/msg.c
has had its own version of err() for a long time, but this somehow
didn't cause problems until the update to awk-3.1.0.

Replace memory leaking instances of realloc with non-leaking reallocf.
In some cases replace if (a == null) a = malloc(x); else a =
realloc(a, x); with simple reallocf(a, x). Per ANSI-C, this is
guaranteed to be the same thing.

I've been running these on my system here w/o ill effects for some
time. However, the CTM-express is at part 6 of 34 for the CAM
changes, so I've not been able to do a build world with the CAM in the
tree with these changes. Shouldn't impact anything, but...

_err() -> err().

Add stringlist functions from NetBSD. (required for the new ftp(1)
Obtained from: NetBSD