Answer:
#!/bin/bash
if [ -z "$1" ] || [ -z "$2" ]
then
echo "invalid arguments"
exit 1
fi
filename="$1"
extension="$2"
cnt=1
for file in *. $extension
do
echo "renaming $file to $filename $cnt.$extension"
mv -i "$file" "$filename$cnt. $extension" #prompt before overwriting a file
cnt=$(( $cnt + 1 ))
done
Step-by-step explanation: