#!/bin/sh
#
# rename *.oldsuffix files, changing oldsuffix to newsuffix
#
if [ -z "$2" ]
then
    echo usage is `basename $0` oldsuffix newsuffix
    exit 1
fi

# first attempt -- fails for files with names containing spaces
#for f in `ls *.$1`
#do
#    oldname="$f.$1"
#    newname=`basename $f .$1`.$2
#    if [ "$oldname" = "$newname" ]
#    then
#        echo names are the same
#    else
#        mv -v "$oldname" "$newname"
#    fi
#done

ls *.$1 | while read line
do
    oldname="$line"
    newname=`basename "$oldname" .$1`.$2
    #another way
    #newname=`echo $oldname | sed "s/\.$1/.$2/"`
    mv -v "$oldname" "$newname"
done