MFC 360283:

Fix invalid use of macros and two typos

It turns out that currently mandoc(1) is not handling Fl in Ss
correctly (maybe it never was). Let's just replace "Fl S \&Ss ..."
with "-S ...". After all, this subsection title is stylized anyway, so Fl
is not that helpful.

MFC r357563: env(1): grow -L user/class and -U user/class options

This allows one to set the environment of the specified user either from
login.conf alone (-L) or both login.conf and ~/.login_conf if present (-U).

This is a supporting feature to allow service(8) to pull in the environment
of the "daemon" class before invoking the rc script.

MFC r354450: Add -0 option to ENV(1)

With the -0 option added to ENV(1), some ports will no longer require genv
from sysutils/coreutils.

MFC r313659-r313673

r313659:
Remove space at and of line

Reported by: make manlint
MFC after: 2 days

r313660:
Remove empty Li

Reported by: make manlint
MFC after: 2 days

r313661:
Escape Ss to avoid confusion by mdoc parser with the Ss macro

Reported by: make manlint
MFC after: 2 days

r313662:
Add missing -width after -Bl -tag

Reported by: make manlint
MFC after: 2 days

r313663:
Add missing section after .Xr reference

r313664:
Escape No to avoid confusion with the No macro

r313665:
Remove useless .Pp after the .Sh macro and remove empty line

r313666:
Remove empty space at EOL and escept Ed

r313667:
Remove spaces at EOL and sort correctly the SEE ALSO section

r313668:
Add missing section in manpage reference

r313669:
Properly use .An macro before Authors name

r313670:
Escape Sm to avoid confusion with Sm macro

r313671:
Use correct date format

r313672:
Remove useless Li macro

r313673:
Remove spaces at end of line

Reported by: make manlint

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Remove the advertising clause from UCB copyrighted files in usr.bin. This
is in accordance with the information provided at
ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change

Also add $FreeBSD$ to a few files to keep svn happy.

Discussed with: imp, rwatson

Update the date on the man-page to reflect the date that the '-u name'
change was committed, instead of when I had first started writing it...

Add the '-u name' option to the env command, which will completely unset
the given variable name (removing it from the environment, instead of
just setting it to a null value).

PR: bin/65649
MFC after: 2 weeks

Tidy up the markup.

Approved by: re (blanket)
OK'ed by: gad

Put in a more descriptive heading for the `env' command.

Noticed by: Matthew D Fuller
Approved by: re (blanket `env')

Undo r1.14 to env.c. While it is unusual for environment variables to
start with a '/', they are more supported (by POSIX and SUSv3) than
filenames which have an '=' in them.

Noticed by: tjr
Approved by: re (blanket `env')

Add the '-S' and '-P' options. The '-S' option can be used to split
apart a string, and supports some text substitutions. This can be
used to provide all the flexibility (and more!) that was lost by recent
changes to how the kernel parses #!-lines in shell scripts.

The '-P' option provides a way to specify an alternate set of directories
to use when searching for the 'utility' program to run. This way you can
be sure what directories are used for that search, without changing the
value of PATH that the user has set. Note that on FreeBSD 6.0, this
option is worthless unless the '-S' option is also used.

Approved by: re (blanket `env')

Added the EXIT STATUS section where appropriate.

Language and markup polishing.

Fix grammar bogon.

Removed (after the env(1)/printenv(1) split) extraneous arguments
to the .Nm macro.

Split the env(1) manpage off from printenv(1); there is not much point
in keeping them together. Mention that printenv is obsolescent.