Edit entry if not equal

Shell Programming and Scripting
1

Ok here's the scenario, i have a ll.conf file and masterlist.

#cat ll.conf
123456
banner 1234
abcdefghi

#cat masterlist
abcdefghi
banner 123456789

what script to change ll.conf banner 123456789 from banner 1234 if they are not equal.
the final output will looks like this.

#cat ll.conf
123456
banner 123456789
abcdefghi

2 
{
 read
 read banner num
} < masterlist
sed "s/^banner .*/banner $num" ll.conf
3

sed: 0602-404 Function s/^banner .*/banner cannot be parsed. thanks for the effort but error,

4

Sorry; typo:

{
 read
 read banner num
} < masterlist
sed "s/^banner .*/banner $num/" ll.conf
5

thanks i got it, is it possible if we could not change it,like for exzample it will ask if we want to change it by pressing yes or no, then if they are equal it will pop a message "they are equal",if they are not it will me an option if i will change it or not.