Usort an array on modified date in php when date is identical
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I am trying to sort my array of images by last modified date using the following line.

    usort($temp_files, create_function('$a,$b', 'return filemtime($a) - filemtime($b);'));

My page is setup to display one image then 4 additional images next to it. But a lot of the images have the same last modified date on the server and I do not have much control over those since the end client uploads them himself. Is there anyway to get around that when the date is identical?