This is because the localtime function returns 0-based month. ie., 10th month is returned as 9. 1st month is returned as 0, and so on. To fix this, you just have to add 1 to the month.

And another observation is that you are not using sprintf to format your date, which makes it a bit messy.

Have a look at the following simpler version of get date, which uses sprintf to format number with leading 0.

sub Today()
{
    my ($day, $month, $year) = (localtime)[3,4,5];
    return sprintf "%04d%02d%02d", $year + 1900, $month+1, $day;
}
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Your code can be rewritten as

sub getdate {
my ($min, $hr, $day, $mon, $yr) = (localtime($filedate))[1,2,3,4,5];
$filedate = sprintf "%02d-%02d-%04d", $mon+1, $day, $yr+1900;
$filetime = sprintf "%02d:%02d:00", $hr, $min;
}
[download]

cheers. Roger