use Date::Calc qw(:all);

$date= '10/24/2000';

$MM = substr($date,0,2);
$DD = substr($date,3,2);
$YYYY= substr($date,6,4);


$Dd = -1;

      ($year,$month,$day) =  Add_Delta_Days($YYYY,$MM,$DD, $Dd);


$prev_day = join('/',$month,$day,$year);

print "$prev_day";
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And if you want to stick to modules that are included in the Perl core (so no trip to CPAN), you can accomplish this with Time::Local's timelocal and POSIX's fab-oo strftime ...

use Time::Local;
use POSIX qw/ strftime /;

my $today     = '10/24/2000';

my $days_ago  = 1;

my $yesterday = do {

    my($m,$d,$y)  = split( m'/' => $today );

      # I use 12 as the hour here, so there's no 
      # confusion about daylight savings.

    my $t  = timelocal( 0, 0, 12, $d, $m - 1, $y - 1900 );
       $t -= $days_ago * 24*60*60 ;

    strftime( '%m/%d/%Y' => localtime($t) );
};

print "$today $yesterday";
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Looks a lot like the Time::Piece (alt.) example, no? :)

    --k.

Take a look at some of the date modules, including Date::Calc or even Class::Date. An example of the latter would look like:

 use strict;
 use Class::Date;

 my ( $m, $d, $y ) = split( '/', '10/24/2000' );
 my $d = Class::Date->new([ $y, $m, $d ]);
 my $before = $d - '1D';
 print "Day before: $before";
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Chris
M-x auto-bs-mode

#!/usr/bin/perl -wT
use strict;
use Time::Piece;

my $date    = "10/24/2000";
my $daysago = 1;
my $format  = "%m/%d/%Y";
my $newdate =
  ( Time::Piece->strptime( $date, $format ) - $daysago * 24*60*60 )
  ->strftime($format);

print "$date - $daysago => $newdate\n";

__END__

10/24/2000 - 1 => 10/23/2000
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-Blake

Check out Date::Business or Date::Manip

<cite>Just a tongue-tied, twisted, earth-bound misfit. -- Pink Floyd</cite>

($d,$m,$y)=(localtime((time-60*60*(12+(localtime)[2]))))[3,4,5];
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That will break for time zones that use daylight savings time. On the days where the clock is set back an hour, you will not be subtracting enough from time() to make that work. Better to use Date::Calc, as suggested elsewhere in this thread.

($d,$m,$y)=(localtime((time-60*60*(12+(localtime)[2]))))[3,4,5];
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Edit 2/16/02 dws to add <code> tags

Let's dissect it:

time-60*60*(12+(localtime)2)
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That piece is taking the current time and subtracting enough seconds to get to the previous day, accounting for any daylight savings time differences. Since you don't care about the time -- just the date -- that trailing part ((12+(localtime)2)) is just taking you back 12 hours before the start of the current day. A safe way to eliminate daylight savings time issues when only a date is needed. All of this is based on the fact that time() deals with the epoch, which is expressed in seconds: 12 hours times 60 minutes per each hour times 60 seconds per each minute yields the total number of seconds 12 hours before the start of the current day. Let's let this entire result be represented by X.

($d, $m, $y) = (localtime(X))3,4,5;
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Is then getting the day/month/year from the calculated epoch time, represented above as X.