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QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
Programming
Getting Started with QNX Neutrino
Getting Started with QNX Neutrino: A Guide for Realtime Programmers is intended to introduce you to the QNX Neutrino RTOS and help you develop applications and resource managers for it.
Processes and Threads
The kernel's role
The house analogy is excellent for getting across the concept of synchronization, but it falls down in one major area. In our house, we had many threads running simultaneously. However in a single-processor system, only one thing can run at once.

QNX Momentics IDE User's Guide
This User's Guide describes version 7.1 of the Integrated Development Environment (IDE) that's part of the QNX Momentics tool suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
- Quickstart Guide
- OS Components & Operations
- Audio & Graphics API
- Multimedia
- Networking Middleware
- Programming
  - Getting Started with QNX Neutrino
    Getting Started with QNX Neutrino: A Guide for Realtime Programmers is intended to introduce you to the QNX Neutrino RTOS and help you develop applications and resource managers for it.
    - Processes and Threads
      - Process and thread fundamentals
        Before we start talking about threads, processes, time slices, and all the other wonderful scheduling concepts, let's establish an analogy.
      - The kernel's role
        The house analogy is excellent for getting across the concept of synchronization, but it falls down in one major area. In our house, we had many threads running simultaneously. However in a single-processor system, only one thing can run at once.
        Single CPU
        Let's look at what happens in the real world, and specifically, the economy case where we have one CPU in the system. In this case, since there's only one CPU present, only one thread can run at any given point in time. The kernel decides (using a number of rules, which we'll see shortly) which thread to run, and runs it.
        Multiple CPU (SMP)
        If you buy a system that has multiple, identical CPUs all sharing memory and devices, you have an SMP box (SMP stands for Symmetrical Multi Processor, with the symmetrical part indicating that all the CPUs in the system are identical). In this case, the number of threads that can run concurrently (simultaneously) is limited by the number of CPUs. (In reality, this was the case with the single-processor box too!) Since each processor can execute only one thread at a time, with multiple processors, multiple threads can execute simultaneously.
        The kernel as arbiter
        So who decides which thread is going to run at any given instant in time? That's the kernel's job.
        Kernel states
        We've been talking about running, ready, and blocked loosely—let's now formalize these thread states.
      - Threads and processes
        Let's return to our discussion of threads and processes, this time from the perspective of a real live system. Then, we'll take a look at the function calls used to deal with threads and processes.
      - More on synchronization
      - Scheduling and the real world
        So far we've talked about scheduling policies and thread states, but we haven't said much yet about why and when things are rescheduled.
    - Message Passing
      In this chapter, we'll look at the most distinctive feature of QNX Neutrino, message passing. Message passing lies at the heart of the operating system's microkernel architecture, giving the OS its modularity.
    - Clocks, Timers, and Getting a Kick Every So Often
      It's time to take a look at everything related to time in the QNX Neutrino RTOS. We'll see how and why you'd use timers and the theory behind them. Then we'll take a look at getting and setting the realtime clock.
    - Interrupts
      In this chapter, we'll take a look at interrupts, how we deal with them under QNX Neutrino, their impact on scheduling and realtime, and some interrupt-management strategies.
    - Resource Managers
      In this chapter, we'll take a look at what you need to understand in order to write a resource manager. Resource managers are another distintive feature of QNX Neutrino that allow you to access services through standard POSIX calls.
    - Sample Programs
      This appendix contains the complete versions of some of the sample programs discussed in this book.
    - Glossary
  - Programmer's Guide
    The QNX Neutrino Programmer's Guide covers a variety of topics that might interest developers who are building applications that will run under the QNX Neutrino RTOS.
  - The QNX Neutrino Cookbook: Recipes for Programmers
  - Writing a Resource Manager
- Sensor Framework
- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX Neutrino RTOS system and developers who want to create a QNX Neutrino resource manager free from vulnerabilities.
- Utilities & Libraries
QNX Hypervisor
The QNX Hypervisor allows you to run multiple OSs on a target system so you can separate critical and non-critical functions, support a wide variety of applications, and reduce hardware costs.
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX software in Amazon Web Services (AWS) and Microsoft Azure (Azure).
QNX Advanced Virtualization Frameworks User's Guide
This User's Guide is aimed at all systems integrators and developers who want to design and build embedded systems using the QNX Advanced Virtualization Frameworks.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation and explains how to obtain technical support.

The kernel's role

The house analogy is excellent for getting across the concept of synchronization, but it falls down in one major area. In our house, we had many threads running simultaneously. However in a single-processor system, only one thing can run at once.

Page updated: March 12, 2026