Shell Programming and Scripting

if [ $# -ne 1 ] || [ ! -d $1 ]
then
    echo "usage: $0 <directory>"
    exit 1
fi
find $1 -type f -ls | awk '
  $8 > 0 {
     gsub("\\\\ ", SUBSEP); F=$12; gsub(SUBSEP, " ", F); # Deal with space(s) in filename
     if($8 in sizes) {
         sizes[$8]=sizes[$8] SUBSEP F;
         dup[$8]++
     } else sizes[$8]=F
  }
  END {for(i in dup) print sizes[i] }' | while read
do
   # SUBSEP (34 Octal) between each filename that has same size
   # Change IFS to Load Array F with a group of 2 (or more) files 
   OIFS="$IFS"
   IFS=$(printf \\034)
   F=( $REPLY )
   IFS="$OIFS"
   i=0
   while [ $i -lt ${#F[@]} ]
   do
       let j=i+1
       while [ $j -lt ${#F[@]} ]
       do
           cmp -s "${F[i]}" "${F[j]}" &&
               echo "\"${F[i]}\"" and "\"${F[j]}\"" are identical
           let j=j+1
       done
       let i=i+1
    done
done