I am getting dates in a YYMMDD format. I need to find out if they are more than X days in the past. I want to install the Date::Calc module but it requires an ANSI C compiler. The boss says I can use anything that I can build with straight perl or nmake.exe (Windows systems), but cannot install an ANSI C compiler. Since we don't currently use it, he doesn't want it on production servers.

Are there other modules that would allow this? Here's a snippet of what I tried, but it didn't work: 

use Time::Local;
use constant MAX_AGE => 20;

# Other code here

sub older_than_MAX_AGE {
    my $date              = _convert_date( $_[0] ); # convert yymmdd t
+o epoch seconds
    my $max_epoch_seconds = MAX_AGE * 60 * 60 * 24; # MAX_AGE should b
+e days.  This converts it to seconds.
    my ( $day, $month, $year ) = (localtime)[3..5];
    $year += 1900;
    my $today             = timelocal( 0,0,0, $day, $month, $year );
    my $cutoff_date       = $today - $max_epoch_seconds;
    return $date < $cutoff_date ? 1 : 0 ;
}

sub _convert_date {
    # This takes a date in YYMMDD format and converts it to epoch seco
+nds (assumes 12:00:00 midnight)
    my $date = shift;
    my ( $year, $month, $day ) = ( $date =~ /(\d\d)(\d\d)(\d\d)/ );
    $year += 2000;
    timelocal( 0,0,0,$day,$month,$year );
}

[download]
When I pass "older_than_MAX_AGE" the date of 010329, I get the following data:

$cutoff_date '986281200'
$date '988527600'
$max_epoch_seconds 1728000
$_[0] '010329'
$today '988009200'

As you can see, it says that the date that I am passing in is *newer* than today: 988527600 > 988009200, even though today is 010423 and the date passed in is 010329. Can anyone see what I'm doing wrong?

Thanks, J. Atzger

In reply to How Many Days in the Past? by Anonymous Monk

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