I wrote a 5m shellscript that walks throught pkgsrc tree looking for files and tries to give a list of the installed packages. This is useful on pkgdb destruction or lost packages.

I think that anybody could be interested on that:

#!/bin/sh

#
# pkgsrc db regenerator
#

PKGSRC=/usr/pkgsrc
PREFIX=/usr/pkg
MARGIN=5

cd ${PKGSRC}
echo "Loading pkgsrc tree...";
DIRS=`find . -type d -maxdepth 2 -mindepth 2`
echo "Comparing PLIST against /usr/pkg prefix... ";

for A in ${DIRS} ; do
	if [ -e "$A/PLIST" ]; then
		FILES=`grep -v -e ^\@ $A/PLIST`;
		TOTAL=0;
		FOUND=0;
		for B in ${FILES}; do
			if [ -e "${PREFIX}/${B}" ]; then
				FOUND=`echo ${FOUND}+1|bc`;
			fi
			TOTAL=`echo ${TOTAL}+1|bc`;
		done

		# Margin implementation
		test ${TOTAL} -gt ${MARGIN}
		if [ "$?" = "0" ]; then
			FOUNT=`echo ${FOUND}+${MARGIN}-${TOTAL}|bc`;
			test ${FOUNT} -gt 0
		else
			true
		fi

		if [ "$?" = "0" ]; then
		if [ ! ${FOUND} = "0" ]; then
			echo "$A (${FOUND}/${TOTAL})"
		fi
		fi
	fi
done