Shell Programming and Scripting

#!/bin/bash
D=`date +'%d'`
oldday=`expr $D - 2`
rm /sent/data-$oldday*
echo $oldday

find /sent -mtime 2 -exec rm {} \;

date -d 'now -2 days' '+%d%m%y'

root@srv1 # date -d 'now -2 days' '+%d%m%y'
date: illegal option -- d
usage:  date [-u] mmddHHMM[[cc]yy][.SS]
        date [-u] [+format]
        date -a [-]sss[.fff]

#!/bin/ksh


days_ago()
{
  perl -e  '
	# take 86400 * # of days from right now in epoch seconds
		 $yestertime = time - (86400 * $ARGV[0]);
		 $month = (localtime $yestertime)[4] + 1;
	# day of the month
		 $day = (localtime $yestertime)[3];
	# year
		 $year = (localtime $yestertime)[5] + 1900;
	# touch -t date format  YYYMMDD0000
		 printf( "%4d%02d%02d0000\n", $year, $month, $day);  '  $1
}

#usage
# 2 days ago
touch -t $(days_ago 2) dummy
find . -type f ! -newer dummy -exec ls -l  {} \;