#!/bin/bash
if [ $# -ne 2 ]; then
   echo "Usage myScript dirName extension"
   exit 0
fi
if [ ! -d "$1" ]; then
   echo "Directory $1 does not exist. Aborting ... "
   exit 0
fi
for file in "$1"/*; do
   if [[ $file == *.$2 ]]; then 
       echo $file
   fi  
done