#!/bin/sh
#
# Shell script for name changing source code
#

if [ ! $# = 3 ]; then
   echo "Usage: chg <source> <old_word> <new_word>"
   echo "       (this script changes <source> directly)"
   exit 1
fi

if [ ! -r $1 ]; then
   echo "source file ->$1<- doesn't exist..."
   exit 1
fi

if [ ! -r $1.BAK ]; then
   echo "creating backup file: $1.BAK"
   cp $1 $1.BAK
fi

sed "s/$2/$3/g" $1 > out
#sed s/$2/$3/ $1 > out
rm $1
mv out $1
echo "done!"