Having worked with the terminally ill for some considerable time, this scenario really pisses me off. The doctors assumption that your friend has suddenly lost the power of reason by telling his family before him is contemptible and cowardly ( and make no mistake, doctors put this intolerable burden on the family because they don't want the job themselves!).

As one or two people have already said, there is a good chance he already knows however he is almost certain to 'collude' with the family in the fiction to spare their feelings.What will then happen is the family won't get the chance to say what they might have said had the fiction not been in place and the patient won't feel he has permission to do so either.Everybody loses.

I am so sorry this is happening to you and your friend Charcloth,I can't tell you how many times I've seen it and had to stand by to watch people make a not so good ending because of it.