lib: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

Remove $FreeBSD$: one-line .c pattern

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

Use __SCCSID() for SCCS IDs.

- Define NO__SCCSID in CFLAGS to preserve existing behavior of omitting
SCCS IDs by default.
- While here, fix the $FreeBSD$ in pw_util.c to use __FBSDID.

General further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

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.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

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 r202500:

Fix a regression that was introduced in r191882.

I changed login_tty() to only work when the application is not a session
leader yet. This works fine for applications in the base system, but it
turns out various applications call this function after daemonizing,
which means they already use their own session.

If setsid() fails, just call tcsetsid() on the current session.
tcsetsid() will already perform proper security checks.

Reported by: Oliver Lehmann

Fix a regression that was introduced in r191882.

I changed login_tty() to only work when the application is not a session
leader yet. This works fine for applications in the base system, but it
turns out various applications call this function after daemonizing,
which means they already use their own session.

If setsid() fails, just call tcsetsid() on the current session.
tcsetsid() will already perform proper security checks.

Reported by: Oliver Lehmann
MFC after: 1 week

Add tcsetsid(3).

The entire world seems to use the non-standard TIOCSCTTY ioctl to make a
TTY a controlling terminal of a session. Even though tcsetsid(3) is also
non-standard, I think it's a lot better to use in our own source code,
mainly because it's similar to tcsetpgrp(), tcgetpgrp() and tcgetsid().

I stole the idea from QNX. They do it the other way around; their
TIOCSCTTY is just a wrapper around tcsetsid(). tcsetsid() then calls
into an IPC framework.

- Import the HEAD csup code which is the basis for the cvsmode work.

Remove California Regent's clause 3, per letter

ANSIfy, WARNSify, CONSTify. Bit of style(9)-ify.

Tidy up. Sort headers.

Add __FBSDID()s to libutil

$Id$ -> $FreeBSD$

Now take stdio.h out of files that don't require it.

All these have to include stdio.h now.

Protect the copyright comments from reformatting by
indent and make this compile -Wall clean like the
Makefile suggests that it should. :)

Pointed out by: Bruce Evans <bde@zeta.org.au>

Bump libutil revision after recent addition of setproctitle().

Install (optional) libutil.h with prototypes for the functions and
document this in the man page.

minor cleanups to the various routines, include the prototype file, declare
return codes etc.

BSD 4.4 Lite Lib Sources