This changes the OK / Cancel buttons into Auto / Manual / Cancel, with
Auto being the default. Manual behaves like OK used to, i.e. presents a
series of dialogs asking exactly how to configure the interface, and
Cancel is unchanged, exiting with exit code 1. Auto will attempt to
configure IPv4+DHCP and IPv6+SLAAC with no interaction, failing only if
neither can be configured, thereby supporting all of IPv4-only,
IPv6-only and dual-stack environments. If at least one DNS server is
provided, it will also skip asking for DNS settings, otherwise it will
act like Manual mode for the purposes of DNS settings and prompt. For a
standard dual-stack environment this cuts down the number of netconfig
dialogs from 6 (interface, IPv4, DHCP, IPv6, SLAAC, DNS) to just the
first one.

Reviewed by:	brooks
Differential Revision:	https://reviews.freebsd.org/D43731

The replacement of echo >> with sysrc -f used sysrc key value, which
means "read variables key and value" and thus did nothing useful (and in
fact emitted errors to the log about neither existing). Instead use the
correct sysrc key=value form so the installed system comes back up with
working networking.

Fixes:	60b37735f305 ("bsdinstall netconfig: avoid duplicate entries in rc.conf")

This uses sysrc to write and update configuration variables in the
temporary configuration file for network access, ._rc.conf.net. This
replaces the previous mechanism, which was simply appending new values
as they were updated.

PR:		212396
Reviewed by:	emaste
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D42194

Throughout the bsdinstall script fd 3 is used by f_dprintf (set through
$TERMINAL_STDOUT_PASSTHRU). In several places in the bsdinstalls scripts,
we use fd 3 to juggle stdout when calling out to other tools, which can
cause the installer to fail with a "Bad file descriptor" error when
f_dprintf attempts to use it.

This commit replaces all constructs like this:

    exec 3>&1
    SOME_VARIABLE=$(some command 2>&1 1>&3)
    exec 3>&-

With:

    exec 5>&1
    SOME_VARIABLE=$(some command 2>&1 1>&5)
    exec 5>&-

PR:			273148
Reviewed by:		corvink
Fixes:			1f7746d81f53447ac15cc99395bb714d4dd0a4da ("bsdinstall: stop messing with file descriptors")
MFC after:		1 week

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

Approved by:		allanjude, asiciliano
Differential Revision:	https://reviews.freebsd.org/D35197
Sponsored by:		Rubicon Communications, LLC ("Netgate")

Replace (LGPL) dialog utility with (BSD-2-Clause) bsddialog utility.

Reviewed by:		bapt
Differential Revision:	https://reviews.freebsd.org/D35267

After an installation restart (for error or choice) dhclient does not
rebuild resolv.conf so `dialog --mixedform' of "Resolver Configuration"
in bsdinstall/scripts/netconfig draws empty forms. It causes a bad UX,
to see PR262262. Fixed resetting the interface before to run dhclient.

PR:			262262
Reviewed by:		bapt
Differential Revision:	https://reviews.freebsd.org/D35094

PR:		205821
Reported by:	mjg
MFC after:	2 weeks
Sponsored by:	Klara Inc.
Event:		July 2020 Bugathon

PR:		205821
Submitted by:	William Orr <will@worrbase.com>
MFC after:	2 weeks
Sponsored by:	Klara Inc.
Event:		July 2020 Bugathon
Differential Revision:	https://reviews.freebsd.org/D14572