#!/bin/bash
pth="$1"
((keep=45))

if [[ "X$pth" == 'X' ]]
 then
    echo "usage: $0 path"
    exit
 fi

cd ${pth}
pwd
cnt=$(ls -1 | grep -v 'dirvish' | grep -v current | grep -v lost+found | grep -v mlocate | wc -l)
((n = cnt - keep))
ls -1 | grep -v 'dirvish' | grep -v current | grep -v lost+found | grep -v mlocate | head -${n} | while read dir
 do
    echo $dir
    file="${dir}/summary"
    line=$(grep '^Expire:' ${file})
    newline="Expire: +45 days == 2014-05-08 03:30:39"
    echo "mv -f ${file} ${file}.tmp"
    mv -f ${file} ${file}.tmp
    echo "cat ${file}.tmp | sed \"s/${line}/${newline}/\" \> ${file}"
    cat ${file}.tmp | sed "s/${line}/${newline}/" > ${file}
 done