In this paper we propose a new approach to the description of a network of interacting processes in a traditional programming language. Special programming languages or extensions to sequential languages are usually designed to express the semantics of concurrent execution. Using libraries in C++, Java, C#, and other languages is more practical way of concurrent programming. However, this method leads to an increase in workload of a manual coding. Besides, stock compilers can not detect semantic errors related to the programming model in such libraries. The new markup language and a special technique of automatic programming based on the marked code can solve these problems. The article provides a detailed specification of the markup language without discussing its implementation details. The language is used for programming of current and prospective multi-core and many-core systems.