[Billing]
LocalIPAddress = 192.168.1.116
ProcessorsNumber = 1
[Plugins]
LocalIPAddress = 192.168.2.116
ProcessorsNumber = 2
[Statistics]
LocalIPAddress = 192.168.3.116
ProcessorsNumber = 1

I manage to read like this:
BILLPROCESSORSNUMBER=`grep -m1 '^[^#][:space:]*ProcessorsNumber' $OLD_CFG | awk -F" = " '{print $2}' |tail -1`

PLUGINPROCESSORSNUMBER=`grep -m2 '^[^#][:space:]*ProcessorsNumber' $OLD_CFG | awk -F" = " '{print $2}' |tail -1`

STATPROCESSORSNUMBER=`grep -m3 '^[^#][:space:]*ProcessorsNumber' $OLD_CFG | awk -F" = " '{print $2}' |tail -1`

But I'm worried if the sections in the config file will switch and the order not preserved ... then the grep -mX and tail will not give me the proper value for the section/parameter I want.

I want to read this values and later to write them back in the new config file with:
sed -e "/\[Billing\]/,/^[^#][:space:]*ProcessorsNumber =/ s-\(^[^#][:space:]*ProcessorsNumber = \)\([^#]*\)-\1$BILLPROCESSORSNUMBER-1" \
This sed works.

So it is alll about how to read correct from the file.

Thanks
Bianca