I was afraid you wanted that one. You can’t really do that. Follow the link for some workarounds. You could also set a variable or a constant in functions.php
, or create a theme option for this. Then use that in your function.
function smbd_cats_by_days ($where="") {
// global $days_limit; // if a variable
// $days_limit = DAYS_LIMIT; // if a constant
// $days_limit = get_option('days_limit',100);
// you have to uncomment one of the above,
// depending on your choice of mechanisms
$where .= " AND post_date < '" . date('y-m-d', strtotime("-{$days_limit} days")) . "'";
return $where;
}
add_filter('posts_where', 'smbd_cats_by_days');