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

+ Remove UNAME_P=$(...) from startup/misc -- already supplied by common.subr
+ Use f_getvar instead of $(eval echo \$$var) -- f_getvar is sub-shell free
+ Add `-e' and `-k var' options to f_eval_catch -- increasing use-cases
+ Use f_eval_catch to display errors on failure -- reducing duplicated code
+ Use f_eval_catch when we need output from a command -- improving debugging
+ Optimize f_isinter of strings.subr for performance -- now sub-shell free
+ Improve error checking on pidfiles -- using f_eval_catch and f_isinteger
+ Use $var_to_set arg of f_ifconfig_{inet,netmask} -- eliminate sub-shells
+ Use f_sprintf instead of $(printf ...) -- consolidate sub-shells
+ Use $var_to_set arg of f_route_get_default -- eliminate sub-shells
+ Add f_count to replace $(set -- ...;echo $#) -- eliminate sub-shells
+ Add f_count_ifs to replace $(IFS=x;set -- ...;echo $#) -- no sub-shells
+ Replace var="$var${var:+ }..." in loops with var="$var ..." with a follow-
  up var="${var# }" to trim leading whitespace -- optimize loops
+ Use $var_to_set arg of f_resolv_conf_nameservers -- eliminate sub-shells
+ Comments for the f_eval_catch function
+ Remove a duplicate `local ... desc ...' in f_device_get_all of device.subr
+ Use $var_to_set arg of f_device_capacity -- eliminate sub-shells
+ Whitespace fixes in f_dialog_init of dialog.subr
+ Optimize f_inet_atoi of media/tcpip.subr for performance -- sub-shell free
+ In several cases, send stderr to /dev/null -- clean up runtime execution
+ Change f_err of common.subr to go to program stderr not terminal stderr,
  allowing redirection of output from functions that use f_err
+ Disable debugging when using f_getvar to get variable argument to
  f_startup_rcconf_map_expand of startup/rcconf.subr
+ Use f_replace_all instead of $(echo ... | tr | sed) -- performance
+ Add a $var_to_set option to f_index_{file,menusel_{command,keyword}} of
  common.subr -- centralize sub-shells

throughout the bsdconfig(8) code. While we're here, add an explicit argument
to lvalue-seeking invocations of "return" that previously had no argument.
Also, consolidate a single instance of double-newline and remove some
comments that are no longer required (given increased readability with new
exit codes).

Approved by:	re (glebius)

wording ("All rights reserved."); I had the casing wrong on many instances.

if a menu addition is made in one plce but forgotten in another).

invocation. Specifically, "top-load" your arguments and in the order in-
which they will be displayed. For example, many [if not all] widgets display
information in the following order, top-to-bottom (visually):

+ backtitle (displayed behind the widget at top-left)
+ title (at the top of the `window')
+ prompt text (just below the title and above whatever widget you choose)
+ Depending on widget, _one_ of the following:
  - menu list
  - radio list
  - check list
  - text input box with initial text
  - [Xdialog(1)] 2x or 3x text input boxes
  - [dialog(1)] a multi-part form
  - progress bar
  - etc. (many more widget choices)
+ buttons (right below the selected widget)
+ [dialog(1)] the hline (displayed at bottom of `window')

NOTE: Xdialog(1) accepts and silently ignores --hline

When building local arguments for your dialog invocation, if the value can't
be cleanly loaded into a local, add "# Calculated below" to the end of the
local declaration while retaining the block order of argument declarations.

Move other local declarations that are not associated with this top-loading
the dialog arguments to right-above where they are first-used.

Also, standardize on the names of the arguments. For example, always use
$prompt (instead of sometimes $msg and sometimes $prompt); use $menu_list
or $shell_list or $radio_list for those respective widgets; ad nauseum.

While we're doing this, flush-out full arguments for many invocations that
were passing NULL strings (making it unapparent if you were staring at this
one invocation what argument that NULL string was supposed to represent).

Last, while we're in startup/rcconf let's remove the unnecessary use of a
GLOBAL (RCCONF_MENU_LIST) for the menu_list.

retrieving stored data (for the --menu, --calendar, --timebox, --checklist,
and --radiolist widgets).

When we (Ron McDowell and I) developed the first version of bsdconfig, it
used temporary files to store responses from dialog(1). That hasn't been
true for some very long time, so the need to always store the return status
of dialog(1) and then call some function to clean-up is long-deprecated. The
function that used to do the clean-up was f_dialog_menutag().

We really don't need f_dialog_menutag() for its originally designed purpose,
as all dialog invocations (even when in a sub-shell) do not use temporary
files anymore.

However, we do need to keep f_dialog_menutag() around because it still fills
the need of being able to abstract the procedure for fetching stored data
provided by functions that display the aforementioned widgets.

In re-designing f_dialog_menutag(), four important changes are made:

1. Rename f_dialog_menutag() to f_dialog_menutag_fetch()
2. Introduce the new first-argument of $var_to_set to reduce number of forks
3. Create a corresponding f_dialog_menutag_store() to abstract the storage
4. Offload the sanitization to a new function, f_dialog_data_sanitize()

NOTE: That last one is important. Not all functions need to store their data
for later fetching, meanwhile every invocation of dialog should be sanitized
(as we learned early-on in the i18n-effort -- underlying libraries will spit
warnings to stderr for bad values of $LANG and since dialog outputs its
responses to stderr, we need to sanitize every response of these warnings).

These changes greatly improve readbaility and also improve performance by
reducing unnecessary forking.