Shell Programming and Scripting

EMPID EMPNAME AGE GENDER DESIGNATION SALARY
101 EMPNAME1 25 M ADMIN 90000
102 EMPNAME2 22 F ASSITANT 20000
103 EMPNAME3 26 M PROGRAMMER 80000

temp=$(mktemp tmp.XXXXX)
temp2=$(mktemp tmp.XXXXX)
temp3=$(mktemp tmp.XXXXX)
read -p "Enter the employee ID, you want to edit" empid
grep -v "$empid" < "$datafile" > $temp
grep "$empid" < "$datafile" > "$temp2"
read -p "Enter Field NO to edit: " fno
if test "$fno" = 1; then
olddata=`cat "$temp2" | awk '{print $1}'`
read -p "Enter new Empid" newempid
sed s/$oldata/$newempid/g < "$temp2" > $temp3
elif test "$fno" = 2; then
olddata=`cat "$temp2" | awk '{print $2}'`
read -p "Enter new name" newname
sed s/$oldata/$newname/g < "$temp2" > $temp3
elif test "$fno" = 3; then
olddata=`cat "$temp2" | awk '{print $3}'`
read -p "Enter new age: " newage
sed s/$olddata/$newage/g < "$temp2" > $temp3
elif test "$fno" = 4; then
olddata=`cat "$temp2" | awk '{print $4}'`
read -p "Enter Gender: " newgen
sed s/$oldata/$newgen/g < "$temp2" > $temp3
elif test "$fno" = 5; then
olddata=`cat "$temp2" | awk '{print $5}'`
read -p "Enter new Designation: " newdes
sed s/$oldata/$newdes/g < "$temp2" > $temp3
elif test "$fno" = 6; then
olddata=`cat "$temp2" | awk '{print $6}'`
read -p "Enter new salaray: " newsal
sed s/$oldata/$newsal/g < "$temp2" > $temp3
fi
mv "$temp3" "$temp2"
cat "$temp2" >> $temp
cat "$temp" | uniq > "$datafile"
rm "$temp"
;;