I modified your function to allow for an additional 'format' argument. 'format' allows you to customize the returned string.

function dateDiff($from,$to,$format='%%D%% d, %%H%% h, %%M%% m, %%S%% s'){
$diff = $to - $from;
$info = array('d'=>0,'h'=>0,'m'=>0,'s'=>0);
if($diff>86400) {
$info['d'] = ($diff - ($diff%86400))/86400;
$diff = $diff%86400;
}
if($diff>3600) {
$info['h'] = ($diff - ($diff%3600))/3600;
$diff = $diff%3600;
}
if($diff>60) {
$info['m'] = ($diff - ($diff%60))/60;
$diff = $diff%60;
}
if($diff>0) {
$info['s'] = $diff;
}
return str_replace(array('%%D%%','%%H%%','%%M%%','%%S%%'),array($info['d'],$info['h'],$info['m'],$info['s']),$format);
}

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