Re: Very interesting analysis of "the state of Emacs"

[Richard M Stallman]

    Good point.  But I don't think it's a problem either: what I meant by
    "multithreading within a single buffer" is that we'd have a lock per
    buffer.  Whenever lisp code enters a buffer, we'd acquire the lock.

What does it mean to "enter a buffer"?  Does calling `set-buffer' do
that?

If it means entering the code of a primitive that directly examines or
alters the buffer contents, I would suggest not allowing a thread
switch inside of them (or most primitives).  If the threads are
implemented explicitly in our C code, switching can happen only where
we want it to happen.  That would avoid lots of problems.  We would
only allow thread switches at places where Lisp code can be run.