plan9rc vars, defaults, and actions

GENERAL NOTE: most plan9.ini variables should produce the same
behavior and the new features are active by default.  Existing
plan9.ini configurations should work as before with little
modifications while automatically creating the 'service' environment.

bootargs follows the normal plan 9 conventions.  choose tcp or local,
with the local specifier providing a path for finding a root file
system from disk, and additional tcp parameters being given to
ipconfig.  local!#S/sdC0/fossil is the default if none is provided.

venti is the same as standard plan9.ini for establishing a connection
to a venti server if needed by a local fossil.

fs and auth are the ip of file auth servers as in standard boot and
plan9.ini

cfs is the pathname of a cfs partition to be used for caching when tcp
booting, if desired

fossil and kfs may be set to specify a given partition

interactive controls whether or not the user will be prompted through
the boot process and given the option to modify any parameters
provided by plan9.ini.  It will default to traditional mode behavior,
set interactive=yes to enable interactive boot or interactive=no for
automatic bootup.  If no bootargs are found, interactive mode is
turned on also.  interactive=traditional emulates the prompts of the
traditional bootup but still follows the plan9rc startup according to
the variables given in plan9.ini.  It prompts for local vs tcp and tcp
root and auth ips if needed only.

startventi is a new variable which allows you to start a venti server
even if this venti is not required for a local fossil.  It defaults to
not starting but it will automatically be changed to yes if the venti
variable begins with # indicating it should be started for a local
fossil.

ramsetup and initscript are new vars that default to =ramskel and
=initskel if not set in plan9.ini.  The ramskel is important to
provide a skeleton fs for basic functionality and shouldn't be changed
unless you have provided a substitude skel.tar in /boot.  The initskel
is optional and acts as a 'cpurc' style init for the independent
service namespace.  Full details on its configuration follow after the
plan9rc vars.

tgzfs is an optional additional set of utilities that can be loaded
from disk into ram.  An example is the tools.tgz which contains a set
of utilities crafted to complement the compiled-in /boot.  If the 9fat
partition is not located at /dev/sdC0/9fat, the fatpath= variable must
be set to tell dossrv the correct pathname of a 9fat partition if a
tgzfs is to be used.

factotum and rootstart default to the value of /env/service if not set
in plan9.ini.  They determine whether factotum will be started in
terminal or cpu mode and whether the cpurc or termrc will be launched.
These behaviors can now be controlled independently of the compiled in
cpu vs.  terminal kernel distinction.

namespace is set by default to 'namespace' and determines the
namespace entered into by the initscript.  The provided namespace is
rooted on the /srv/ramboot fs.  This does not affect the namespace of
"hosted" systems with their own root fs.  You probably don't want to
change this.

ipparams is a variable for setting ipconfig parameters.  It allows
these parameters to be set regardless of whether tcp boot is being
used or a venti is being dialed.  The ipconfig command will not be
issued until necessary or until the initskel initscript.

staylocal is a variable to determine the behavior of the console
following the completion of plan9rc.  The default is to remain in the
namespace used by the script.  Setting staylocal=no causes plan9rc to
fully terminate and return to the environment with only kernel devices
and no ramfs mounted.

tryusb defaults to checking for the possibility of usb boot and
examining partitions found.  set tryusb=no to not run partfs
regardless of whether usb storage is present.

afterfact and afterroot provide a mechanism for additional user
customization.  If these values are given in plan9.ini, the
executables found at the given path will be executed at that point in
the boot process.

---Initskel vars, defaults, andactions ---

binddevs defaults to binding in f t m v L P u U '$' Σ κ =no turns off

hostfactotum defaults to relying on the main system factotum =no
starts a new private factotum -x and prompts for password/dom/auth

netsvc defaults to starting ipconfig if it has not been previously
done =no turns off

hostcsdns defaults to relying on the cs and dns started elsewhere =no
starts cs and dns locally

hubsvc defaults to starting a /srv/hubfs to provide persistent rc in
the independent namespace =no turns off

unprivileged defaults to leaving this environment as a standard
unprileged node =no starts authsrv and keyfs and copies a keyfile from
/adm/keys in the 9fat