find . -name <EXPR> | while read FILE
do
      tmpfile1=$(mktemp)
      tmpfile2=$(mktemp)
      tmpfile3=$(mktemp)
      cp $FILE $tmpfile1
      gruik "$tmpfile1" > "$tmpfile2"
      meuh "$tmpfile2" > "$tmpfile3"
      plop "$tmpfile1" "$tmpfile2" "$tmpfile3" > "$FILE"
      rm -f "$tmpfile1" "$tmpfile2" "$tmpfile3"
done