Summary: The Fork Calculus FC presents a theory of communicating systems in family with CCS, but it differs in the way that processes are put in parallel. In CCS there is a binary parallel operator \(\mid\), and two processes \(p\) and \(q\) are put in parallel by \(p\mid q\). In FC there is a unary fork operator, and a process \(p\) is activated to “run in parallel with the rest of the program” by \(\operatorname{fork}(p)\). An operational semantics is defined, and a congruence relation between processes is suggested. In addition, a sound and complete axiomatisation of the congruence is provided. FC has been developed during an investigation of the programming language CML [J. H. Reppy, “CML: a higher concurrent language”, in: Proceedings of the ACM SIGPLAN 1991 conference on programming language design and implementation, PLDI 1991. New York, NY: ACM Press. 293–305 (1991; doi:10.1145/113446.113470)], an extension of ML with concurrency primitives, amongst them a fork operator.
For the entire collection see [Zbl 0814.00020].