Use a module like Date::Calc and the Delta_Days method. Or Date::Manip. Or use HTTP::Date to translate the date to seconds subtract them and divide by seconds of a day. 
use HTTP::Date;
print ( str2time($date1) - str2time($date2) ) / 3600;

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Boris

In reply to Re: date subtraction by borisz
in thread date subtraction by kasmot

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