Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

Mark usage function as __dead2 in programs where it does not return

In most cases, usage does not return, so mark them as __dead2. For the
cases where they do return, they have not been marked __dead2.

Reviewed by: imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/735

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

various: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

Reassign copyright statements on several files from Advanced
Computing Technologies LLC to Hudson River Trading LLC.

Approved by: Hudson River Trading LLC (who owns ACT LLC)
MFC after: 1 week

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

MFC of r199642

The output of perror(1) is now showing local messages for locales
supported by libc/nls

PR: bin/140499
Approved by: gnn@

The output of perror(1) is now showing local messages for locales
supported by libc/nls

PR: bin/140499
Approved by: gnn@

Use prototype for usage(). This makes perror(1) WARNS=6 clean.

Approved by: gnn

A few more style changes as well as a more broad allowance for
errors to be given by the caller. Change output to be easier
for use in scripts.

Submitted by: bce

Fix a few style(9) nits.

Submitted by: danfe

Add a new program, perror, which takes an errno as a command line argument
and outputs the associated textual message in the same way that
perror(3) would if called within a program.