Here is the code I use
<?php
$zip = new ZipArchive;
$res = $zip->open('file.zip');
if ($res === TRUE) {
$zip->extractTo('myextractdir/');
$zip->close();
echo 'Extracted';
} else {
echo 'failed';
}
?>
It just outputs Extracted, but no files show up. The file is a zip file..