iRMX is an object-oriented real-time operating system (OS). It has a set of coordinated resources, including memory management, concurrency, interrupts, and peripheral devices. These resources are integrated and protected, allowing programmers to develop fast, robust systems.

The book is divided into two parts: “Basics” and “iRMX Concepts and Features.” The first part introduces real-time systems programming, application development, development languages, the Intel 80X86 architecture, and iRMX. The second part covers iRMX in depth: objects and structures, task synchronization, communication, buffer pools, job management, I/O management, device drivers, type managers, network programming in iRMX, and iRMX for Windows. The book also contains four appendices on Softsope III, a terminal support code, stream I/O, and iRMX system calls, respectively. It ends with a good glossary, some references, and an index.

Chapter 1, “Introduction to Real-time and Systems Programming,” briefly describes systems programming, operating systems construction, development tools, real-time systems characteristics, iRMX history, and several types of operating systems. Chapter 2, “Using an iRMX System,” describes the first steps in developing real-time applications with iRMX, focusing on development systems and target systems. It presents the layers of iRMX: the human interface, the nucleus, the basic and extended I/O systems, the application leader, the universal development interface, the C runtime library, iRMX platforms, logging in iRMX, human interface commands, the command language interpreter, files and file management, network files, and error conditions.

Chapter 3, “Developing an Application,” briefly describes application development and develops a sample in iRMX. The chapter covers such topics as text editing, segmentation, automating the development process, and debugging. Chapter 4, “Development Languages,” deals with some characteristics of PLM, C, and assembler that are related to iRMX applications, such as source language issues, runtime considerations, congruence with iRMX, and debugging. Chapter5, “The Intel X86 Architecture,” is based on the idea that an understanding of the processor architecture is necessary to produce efficient applications or even functional code.

Chapter 6, “Fundamental iRMX Objects and Structures,” begins with a discussion of object-based and object-oriented systems. Next, it presents the three fundamental iRMX object types managed by the nucleus (jobs, tasks, and segments) and introduces the memory management and system calls facilities provided by the nucleus. The chapter ends with a description of the system call mechanism, relating it to both the object-based nature of the OS and to the 80X86 architecture.

Chapter 7, “Basic iRMX System Calls,” presents the system calls associated with the key concepts of task, memory, and job management used in developing basic real-time applications for iRMX. Chapter 8, “I/O Management,” deals with data operations, device independence, the I/O model, connection objects, file system structure and management, time-of-day management, and logical names.

Chapter 9, “Extending iRMX: Adding Device Drivers,” talks about how anyone can add their own support for nonstandard devices and incorporate user-written code into the OS. Also described are the logical structure of device drivers; common, random, and terminal drivers; and how to add a device driver to the system. Chapter 10, “Extending iRMX: Adding System Calls and Type Managers,” examines the resources provided by the nucleus for adding new system calls and type managers to the system.

Chapter 11, “iRMX Network Programming,” enables the reader to develop programs that use the network directly. It describes a network model, the iRMX networking context, network mechanisms, transport address buffers, the block interface to the Intel Network Architecture, a datagram example, virtual circuit operations, name server operations, network management facilities, and data link operations. Chapter 12, “iRMX for Windows,” deals with console ownership, file system compatibility, interrupt management, system call compatibilities, memory management, VM86 protected mode extensions, dynamic data exchange, network compatibility, and runtime configuration.

The book’s structure is supportive for both beginners (each chapter has an overview of its topic) and advanced readers. For practical use, it is full of examples in PLM, C, and assembler, so that it may be used effectively to quickly build applications. The book can be the basis of an excellent laboratory course for those who want to study and experiment deeply with a real-time OS and its applications. The book equips its readers with both theory and practice, since iRMX is available on relatively inexpensive PC platforms.