date() should not be used to express duration

the function calculate_duration, in read_status.php uses duration to evaluate the result of one timestamp being subtracted to another.

The result is actually a date early in the unix epoch, which I don't think is the intended effect.

I've adapted the function code below, and the output to exemplify the problem.

<?php
$beginning = '1295908827';
$now = time();
$duration = ($now - $beginning);
$duration_in_minutes = ( $duration / 60 );
print("Duration of outage in minutes: $duration_in_minutes <br/>");
$original_duration = date('d\d-H\h-i\m-s\s', $duration);
$epoch_duration = date('r', $duration);
print("Date in unix epoch format: $epoch_duration <br/>");
print("duration as it shows up in vshell: $original_duration <br/>");
?>

Here is what I get in my browser, after running it on my server:

Duration of outage in minutes: 213.01666666667
Date in unix epoch format: Wed, 31 Dec 1969 22:33:01 -0500
duration as it shows up in vshell: 31d-22h-33m-01s

What you need is something like the code here, but I'm not sure what the licensing terms for this site are.

http://snipplr.com/view.php?codeview&id=2711