What can use for DateTime::diff() for PHP 5.2?

Question

Is there any function equivalent to DateTime::diff() in PHP 5.2?

My local server is PHP 5.3 and using DateTime::diff(). then I found that my live site uses PHP 5.2 a

Answer 1

Spudley's answer doesn't work for me--subtracting any DateTime from another gives 0 on my system.

I was able to get it to work by using DateTime::format with the 'U' specifier (seconds since Unix epoch):

$start = new DateTime('2010-10-12');
$end = new DateTime();
$days = round(($end->format('U') - $start->format('U')) / (60*60*24));

This works on both my dev system (5.3.4) and my deployment system (5.2.11).