Shell Programming and Scripting

old_name1 new_name1
old_name2 new_name2
old_name3 new_name3

Employee name: old_name1
Employee name: old_name2
Employee name: old_name3

#! /bin/sh -vx
for i in FileA
do
OLD=`echo $i | awk '{print $1}'`
NEW=`echo $i | awk '{print $2}'`

sed "s/$OLD/$NEW/g" FileB >> FileB.new
done

while read i
do
 old=`echo $i | awk '{print $1}'`
 new=`echo $i | awk '{print $2}'`

done < FileA

for i in fileA; do

for i in $(cat fileA); do

while read old new; do
  sed -n "s/$old$/$new/p" FileB
done < FileA > FileB.new

awk 'NR==FNR {A[$1]=$2;next} {$3=A[$3]} 1' FileA FileB > FileB.new

#!/bin/ksh
typeset -A newname;
while read old new; do
 newname[$old]=$new
done < FileA

while read field1a field1b empl;do
  echo "$field1a $field1b ${newname[$empl]}"
done < FileB > FileB.new

sed -n "s/$old$/$new/p"