M3. Compare the main features of CSP and ADA style rendevous.



M4. Compare the Linda tuple-space with similar features in either
    Lisp, Prolog, or a relational database language such as SQL.



M5. Suppose you have asynchronous message passing, where the
    sender does not wait unless the message buffer is full.  Give
    an example of a simple message passing program, either as a
    dataflow diagram or collection of short procedures, that can
    deadlock with buffer sizes of two, but will always work
    correctly with buffer sizes of three or greater.