Yeah? We had an old Unix server that printed its logs in realtime to a dot matrix printer. How are you going to gain control of that?
Read-only is a strong control with lots of solid implementations.
Depending on the make and model, send a reverse feed code and then overwrite with block characters. You will know that something bad happened, but you won't know what.
Depending on the make and model, send a reverse feed code and then overwrite with block characters. You will know that something bad happened, but you won't know what.