Howdy,
I recently found this, which is working for me
add_filter( 'posts_where', 'devplus_attachments_wpquery_where' );
function devplus_attachments_wpquery_where( $where ){
global $current_user;
if( is_user_logged_in() ){
// we spreken over een ingelogde user
if( isset( $_POST['action'] ) ){
// library query
if( $_POST['action'] == 'query-attachments' ){
$where .= ' AND post_author='.$current_user->data->ID;
}
}
}
return $where;
}
Hope it helps!