#!/bin/bash

DIR="$1"

FILES="$DIR/*.txt"

TMP="$DIR/tmp"

for f in $FILES
do
  if [ -f "$f" ]
  then
    echo "Folding $f ..."
        fold -sw 70 $f > $TMP
        mv $TMP $f    
  else
    echo "Oops... \"$f\""
  fi
done