seq(1): Put separator only between the elements.

- Using non-default ('\n') separator will produce an output with the
separator at the end of the output, eg.

% echo "[$(seq -s ' ' 0 2)]"
[0 1 2 ]

- The output should always be followed by a new line character. Currently:

% seq -s ' ' 0 2
0 1 2 %

This change makes seq(1) to behave the same way Linux seq(1):

% echo "[$(seq -s ' ' 0 2)]"
[0 1 2]

% seq -s ' ' 0 2
0 1 2
%

Approved by: oshogbo
Differential Revision: https://reviews.freebsd.org/D43094

Remove $FreeBSD$: one-line .c pattern

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

seq: style(9) cleanup

This is in part for diff reduction with OpenBSD.

Sponsored by: The FreeBSD Foundation

seq: combine asprintf return value checks

Error handling is identical for all of these failure cases.

Sponsored by: The FreeBSD Foundation

seq: fix check for rounding error/truncation

Based on OpenBSD 30f0fd29ba6c:
> We need to compare the printable version of the last value displayed,
> not the floating point representation. Otherwise, we may print the
> last value twice.

PR: 271964
Reported by: Daniel Kolesa
Reviewed by: yuripv
Obtained from: OpenBSD
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40601

spdx: The BSD-2-Clause-NetBSD identifier is obsolete, drop -NetBSD

The SPDX folks have obsoleted the BSD-2-Clause-NetBSD 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

seq: fix style nits

MFC after: 2 weeks

seq: fix potential NULL ptr reference

asprintf(3) allocates memory, and there isn't any guarantee of success.

MFC after: 2 weeks
Obtained from: OpenBSD

seq(1): Require user-provided format strings to contain a conversion

This matches GNU seq, for example.

For users that are looking for similar functionality, 'jot -b foo N' will
print 'foo' N times. See jot(1).

PR: 236347
Reported by: <y AT maya.st>
Sponsored by: Dell EMC Isilon

seq(1): Move long_opts up with globals

seq(1): Provide some long options

These match GNU seq(1) names where applicable for compatibility purposes.

MFC after: 1 month

seq(1): Consistently include 'last' for non-integers

The source of error is a rounded increment being too large and thus the loop
steps slightly past 'last'. Perform a final comparison using the formatted
string values (truncated precision) to determine if we still need to print
the 'last' value.

PR: 217149
Submitted by: Fernando Apesteguía <fernando.apesteguia AT gmail.com>,
Yuri Pankov <yuripv AT icloud.com> (earlier version)
Reported by: Martijn Dekker <mcdutchie AT hotmail.com>
Sponsored by: Dell EMC Isilon

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.

Sync with NetBSD, mainly address NetBSD bug #43355:

Fix valid_format() to be more careful about allowing only valid
printf formats.

Obtained from: NetBSD
MFC after: 2 weeks

Add missing static keywords to seq(1)

Fix typos.

PR: bin/148894
Submitted by: olgeni

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.

Treat numbers after [Ee] a positive number rather than an invalid
one.

Add seq(1), a small utility to generate sequence number.

Obtained from: NetBSD
MFC after: 3 months