Shell Programming and Scripting

var1=`date '+%m/%d/%Y'`
var2=`date '+%m/%d/%Y'`
perl -le 'BEGIN {use POSIX; use Time::Local; $fixed=0}
            $begin = "var1";
            $end   = "var2";
            @x = unpack "A2 A2 A4", $begin;
            $start = timelocal 0,0,0, $x[1], $x[0]-1, $x[2]-1900;
            @y = unpack "A2 A2 A4", $end;
            $end = timelocal 0,0,0, $y[1], $y[0]-1, $y[2]-1900;
            do {
              print strftime "%m%d%Y", localtime $start;
              $olddst = (localtime $start)[8];
              $start += 24*60*60;
              $newdst = (localtime $start)[8];
              if ($newdst == 0 and $olddst != $newdst and !$fixed) {
                $start += 1*60*60; $fixed = 1
              } elsif ($newdst == 1 and $olddst != $newdst and !$fixed) {
                $start -= 1*60*60; $fixed = 1
              }
            } while $start <= $end'

$
$
$ cat -n print_timerange.pl
     1  #!/usr/bin/perl -w
     2  use POSIX;
     3  use Time::Local;
     4  use strict;
     5  my $olddst;
     6  my $newdst;
     7  my $fixed = 0;
     8
     9  # Accept "from" and "to" dates in "MMDDYYYY" format
    10  my $from_date = $ARGV[0];
    11  my $to_date   = $ARGV[1];
    12
    13  # Determine seconds from epoch and set "begin" and "end" values
    14  my @x = unpack( "A2 A2 A4", $from_date );
    15  my $begin = timelocal( 0, 0, 0, $x[1], $x[0] - 1, $x[2] - 1900 );
    16  my @y = unpack( "A2 A2 A4", $to_date );
    17  my $end = timelocal( 0, 0, 0, $y[1], $y[0] - 1, $y[2] - 1900 );
    18
    19  # Loop from "begin" to "end", adding a day's worth of
    20  # seconds in each iteration
    21  while ( $begin <= $end ) {
    22    printf( "%s\n", strftime( "%m%d%Y", localtime $begin ) );
    23    $olddst = ( localtime $begin )[8];
    24    $begin += 24 * 60 * 60;
    25    $newdst = ( localtime $begin )[8];
    26
    27    # Handle jumps due to Daylight Savings. DST start is not really
    28    # an issue here, as we only consider M/D/Y, but I've handled it
    29    # for completeness.
    30    if ( $newdst == 0 and $olddst != $newdst and !$fixed ) {
    31        $begin += 1 * 60 * 60;
    32        $fixed = 1;
    33    }
    34    elsif ( $newdst == 1 and $olddst != $newdst and !$fixed ) {
    35        $begin -= 1 * 60 * 60;
    36        $fixed = 1;
    37    }
    38  }
$
$ # Test for month of November, 2011
$
$ perl print_timerange.pl 11012011 11302011
11012011
11022011
11032011
11042011
11052011
11062011
11072011
11082011
11092011
11102011
11112011
11122011
11132011
11142011
11152011
11162011
11172011
11182011
11192011
11202011
11212011
11222011
11232011
11242011
11252011
11262011
11272011
11282011
11292011
11302011
$
$ # Test for leap year
$
$ perl print_timerange.pl 02202008 03042008
02202008
02212008
02222008
02232008
02242008
02252008
02262008
02272008
02282008
02292008
03012008
03022008
03032008
03042008
$
$ # Test for non-leap year
$
$ perl print_timerange.pl 02202009 03042009
02202009
02212009
02222009
02232009
02242009
02252009
02262009
02272009
02282009
03012009
03022009
03032009
03042009
$
$ # Test for month and year change
$
$ perl print_timerange.pl 12202011 01042012
12202011
12212011
12222011
12232011
12242011
12252011
12262011
12272011
12282011
12292011
12302011
12312011
01012012
01022012
01032012
01042012
$
$

#! /usr/bin/ksh
M=`date +%m`
Y=`date +%Y`
#              ja fe ma ap ma ju ju ag se oc no de
set -A lasts 0 31 28 31 30 31 30 31 31 30 31 30 31
typeset -Z2 dmonth dday
year=2011
while ((year<2015)) ; do
        leap=0
        if ((!(year%100))); then
                ((!(year%400))) && leap=1
        else
                ((!(year%4))) && leap=1
        fi
        lasts[2]=28
        ((leap)) && lasts[2]=29
        month=1
        while ((month<13)); do
                day=1
                while((day<(lasts[month])+1)) ; do
                        dday=$day
                        dmonth=$month
                        echo ${dmonth}${dday}${year}
                       ((day=day+1))
                done
                 ((month=month+1))
        done
        ((year=year+1))
done >date.txt
more date.txt | grep ^$M | grep $Y