%T Repeatable execution of occam programs
%A  Umberto Villano
%E  Janet Edwards
%B Proceedings of WoTUG\-14: Occam and the Transputer\-Current Developments
%X Parallel programs are intrinsically non\-deterministic, and
   therefore the techniques of cyclical debugging that are
   commonly used for sequential programs are not suitable for
   parallel ones. This paper proposes a method for guaranteeing
   the repeatability of occam program behaviour. Saving
   information on the ALT guards selected at run\-time allows
   program replay. i.e. makes it possible to re\-execute the
   program following the same instruction path whatever the
   speed at which each component process is executed. This
   enables the software developer to use tools such as
   debuggers and intrusive monitors to help identify program
   errors. After a discussion on the possible implementations
   of the proposed technique, a prototype tools that allows the
   replat of occam programs within TDS is briefly described.