Experience with Rendezvous (tasking and communication model)

BNR Pascal is a systems programming language that supports the Rendezvous model of tasking and communication. The authors discuss the BNR Pascal tasking model, their positive experience, areas of difficulty, and some of the BNR Pascal extensions that overcome the difficulties. They have found the Rendezvous model to be a powerful system structuring tool. In addition to its obvious uses in concurrency and interprocess communication, Rendezvous is useful in creating dynamic abstractions that are more powerful than traditional ones based on packages or modules. Additionally, tasks permit a capability-oriented style of resource protection. BNR Pascal extensions to the Rendezvous model include: a mechanism for deferring and reinitiating a Rendezvous, a nonblocking message-passing mechanism, and a mechanism for signaling events from lower to higher levels in a system.<>