Deshabilitar el botón en la ventana emergente de swal

function DeleteConfirm(c){
  swal({   
            title: "Want to delete this item?",   
            text: "You will not be able to undo this action!",   
            type: "warning",   
            showCancelButton: true,   
            confirmButtonColor: "#DD6B55",   
            confirmButtonText: "Yes, delete it!",   
            closeOnConfirm: false 
        }, function(){ 
          $(".confirm").attr('disabled', 'disabled'); 

        });
}
Thoughtful Tapir