postinstall reference files without /usr/src

["J. Lewis Muir" <jlmuir%imca-cat.org@localhost>]

Hello, NetBSD Users.

I built the netbsd-6 CVS branch from source using BUILD-NetBSD from
(pkgsrc) sysutils/etcmanage (0.8.2).  This creates a directory named
releasedir which contains the binary sets and kernel.  I then copy these
binary set and kernel files to a target machine where I install them
using INSTALL-NetBSD.  Doing this enables me to not keep a source tree
on the target machine nor build from source on the target machine.

After running INSTALL-NetBSD on the target machine, I want to run
"postinstall check".  Unfortunately, this does not work because
"/usr/src" does not exist.  Looking at the postinstall(8) man page shows
me that there's a '-s' option to specify reference files.  So, I can
do "postinstall -s [RELEASEDIR]/amd64/binary/sets/etc.tgz check" where
[RELEASEDIR] is the path to the releasedir directory I copied over.  For
this form of the '-s' option, it says the etc.tgz file must be specified
and the xetc.tgz file is optional.  My question is, are all the other
set files optional too?  Or put another way, is the '-s' option only for
specifying etc.tgz and xetc.tgz, or is it also intended to be used for
base.tgz, comp.tgz, and so on, and by not specifying those, some checks
will be skipped?

Thank you!

Lewis