Pasted

#!/bin/sh
mkdir /tmp/opkginstalled
cp -r /rom /tmp/opkginstalled
mkdir -p /tmp/opkginstalled/rom/var/lock
opkg list-installed -o /tmp/opkginstalled/rom > /tmp/rom.list
rm -rf /tmp/opkginstalled
 
opkg list-installed > /tmp/all.list
awk 'FNR==NR{a[$0]++}FNR!=NR && !a[$0]{print}' /tmp/rom.list /tmp/all.list > /tmp/custom.list
rm -f /tmp/final.list
OLDIFS=${IFS}
IFS=$'\n'
for l in $(cat /tmp/custom.list); do
    if [ $(grep $(echo $l | cut -d' ' -f1) /tmp/rom.list | wc -l) -eq 0 ]; then
        echo $l >> /tmp/final.list
    fi
done
IFS=${OLDIFS}
cat /tmp/final.list
rm /tmp/rom.list /tmp/all.list /tmp/custom.list /tmp/final.list