'postinstall' vs local configuration: how to preserve automatically?

["John D. Baker" <jdbaker%consolidated.net@localhost>]

Recent-ish updates to 'postinstall' now cause more grief with local
configuration than before.

Specifially, in the past the "obsolete" check would declare

  /var/chroot/spamd

obsolete and remove it if re-run with the "fix obsolete" command.  This
is normally only a problem the first time a system is updated as long
as you remember to re-create "/var/chroot/spamd" afterwards.  On subsequent
updates, that's usually the only "obsolete" item and can be ignored.
If not, it's easy to remove the other obsolete items manually.

On 8.99.* and now netbsd-9, 9.99.*, with the newer fontconfig being
used, I need to make the symlink for "70-no-bitmaps.conf" so I can get
readable (if still tiny) printed output from Firefox for some pages.

As with "/var/chroot/spamd", this mostly made 'postinstall' complain
that "/etc/fonts/conf.d/70-no-bitmaps.conf" was obsolete and remove it
when told to "fix obsolete".  It was simple to re-instate the link or
to ignore the output of 'postinstall' if there were no other obsolete
items.

Lately, the presence of the "70-no-bitmaps.conf" link now also breaks
the 'postintall' fontconfig check.

Is there a way to teach 'postinstall' about local configuration changes
so the various checks won't fail because of them?

(I habitually use 'etcupdate' after every system update, no matter how
small, so 'postinstall' only runs after any changes made during the
'etcupdate' run.)


Thanks.

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