delete uploaded file

I have a function wp_handle_upload() for uploads files.

$file = $_FILES['attachment_icon-' . $i];
$upload = wp_handle_upload($file, array('test_form' => false));

what is a function for delete a uploaded file?

Use wp_delete_attachment( $post_id ) if you have used wp_insert_attachment() before.
$post_id is the attachment ID.

If you haven’t used wp_insert_attachment() a simple …

unlink( $upload['file'] );

… will do it.