#!/bin/bash

rm /opt/tmp/nvramshow

nvram show >> /opt/tmp/nvramshow

i=0

while read -r line; do

val=${line#*=}

var=${line%*=}

if [[ "$val" == "" ]] then

nvram unset $var

fi

i=`expr $i + 1`

if [[ $i == 50 ]] then

sleep 2

i=0

fi

done < /opt/tmp/nvramshow

exit 0