date_dir=`date +%Y-%m-%d -d yesterday`
    echo "$date_dir"
           
    var=`date +%s`;
     
    date=`date --date=@$var +%Y-%m-%d`
     
    echo $date
           
    $ date +%Y-%m-%d -d '-42 days'     # This would subtract 42 days from the current date
    2013-10-30
    $ date +%Y-%m-%d -d '+42 days'     # This would add 42 days to the current date
    2014-01-22
           
    $ date_dir=$(date +%Y-%m-%d -d '-42 days')
    $ echo $date_dir
    2013-10-30