It seems to work (It chokes though on a year like 2202)

That is because localtime is based on the Unix concept of the number of seconds since the epoch of January 1, 1970 and has historically been represented as a 32 bit number which only goes up to the year 2038.

This may work better: 

#!/usr/bin/perl
use warnings;
use strict;

use POSIX qw/ mktime strftime /;

# Get timestamp input from user
print 'Enter a timestamp in mm/dd/yyyy hh:mm:ss format: ';
chomp( my $stamp = <STDIN> );

my ( $month, $day, $year, $hour, $minute, $second ) = $stamp =~ m! (\d
++) / (\d+) / (\d+) \s+ (\d+) : (\d+) : (\d+) !x;

# Get time value in seconds since Epoch with mktime
my $now = mktime $second, $minute, $hour, $day, $month - 1, $year - 19
+00;

my $realanswer = strftime '%m/%d/%Y %H:%M:%S', localtime $now + 300;

print "$stamp + 5 minutes is $realanswer\n";

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In reply to Re: Attack of the killer timestamps by jwkrahn
in thread Attack of the killer timestamps by chexmix

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