#!/bin/sh
# rname

if [ ! -z "$1" -a ! -z "$2" ]; then
  e1=`echo $1 | sed '/[.]/s///g'`
  e2=`echo $2 | sed '/[.]/s///g'`
  for f in `ls *.$e1` 
  do
   if [ -f "`echo $f | sed '/[.]$e1/s//.$e2/g'`" ]; then
    echo "Output `echo $f | sed '/[.]$e1/s//.$e2/g'` file already exists"
   else
    mv $f `echo $f | sed '/[.]$e1/s//.$e2/g'`
   fi
  done
else
  echo "Was expecting parameters of old extension and then new extension used to rename files in current directory"
fi
exit