Re: Recognize mbox files?

[Richard M Stallman]

    So such a check would be needed for _every_ file one does a find-file
    on.

Several such checks are already being done.

         What would happen if you have a legal non-mbox file, that
    contains X-RMAIL-ATTRIBUTES?  

If it starts with a "From ..." line and has an X-RMAIL-ATTRIBUTES: line
sortly after, it would be treated as an Rmail file by default.
That ought to be rather rare, I think.