#!/bin/bash

# Substitutes underscores for blanks in all the filenames in a directory.

ONE=1                     
number=0                  # Keeps track of how many files actually renamed.
FOUND=0

for filename in *         
do
     echo "$filename" | grep -q " "         #  Check whether filename
     if [ $? -eq $FOUND ]                   #+ contains space(s).
     then
       fname=$filename                     
       n=`echo $fname | sed -e "s/ /_/g"`   # Substitute underscore for blank.
       mv "$fname" "$n"                     
       let "number += 1"
     fi
done   

if [ "$number" -eq "$ONE" ]                
then
 echo "$number file renamed."
else 
 echo "$number files renamed."
fi 

exit 0