if ($upto == localtime()) {
    $upto = localtime() + $interval;

[download]

localtime returns a string in scalar context and you can't properly do arithmetic operations on a string. 

$ perl -le'print scalar localtime'
Tue Sep 20 05:32:46 2011

[download]

Perhaps you meant to use time instead?

In reply to Re: cron functionality mimic in perl scripting by jwkrahn
in thread cron functionality mimic in perl scripting by coolfire

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