What's wrong with this Bourne shell script?

[Andy Burgess]

On SunOS 4.03c this script:

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:
total=0
ls -ld * | while read line
do
  set - `echo $line`
  total=`expr $total + $4`
  echo "Subtotal $total"
done
echo "Total $total"
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The subtotal prints increasing numbers as you would expect.
At the end total prints as 0!
What gives?

While you're at it, is there a better way to get the total bytes
of the files in a directory?

Thanks

Andy Burgess