[...]
$session->prompt('/fmcde99999->/');
$session->cmd($set_router) or die $session->error;
$session->prompt('/fmcde99999\(trust-vr\)->/');
$session->cmd($unset_protocol) or die $session->error;
$session->waitfor('/deleting RIP instance, are you sure\? y\/\[n\] /') or die $session->error;
[...]