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QNX Hypervisor and QNX Hypervisor for Safety
The QNX Hypervisor and QNX Hypervisor for Safety products allow 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.
Virtual Device Developer's Guide
The Virtual Device Developer's Guide is intended for use by developers writing virtual devices (vdevs) in a QNX hypervisor system.
About Writing Virtual Devices
This chapter explains the concepts you need to understand before you start writing virtual devices (vdevs) for a QNX hypervisor system.
Prerequisites
Before you write your own vdev you should understand what a vdev is so that you know what it is you are writing.

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX 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 the QNX OS 8.0.
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 Toolkit for Visual Studio Code
This User's Guide describes the QNX^® Toolkit for Visual Studio Code. The guide introduces you to the QNX Toolkit by explaining the QNX development environment and how to build, run, and debug your QNX^® Operating System (OS) applications and systems.
QNX Hypervisor and QNX Hypervisor for Safety
The QNX Hypervisor and QNX Hypervisor for Safety products allow 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.
- User's Guide
  This User's Guide explains the QNX hypervisor architecture and provides instructions for installing and running a QNX hypervisor system, changing system components and configuration, and using hypervisor features such as virtual devices (vdevs).
- Virtual Device Developer's Guide
  The Virtual Device Developer's Guide is intended for use by developers writing virtual devices (vdevs) in a QNX hypervisor system.
  - About Writing Virtual Devices
    This chapter explains the concepts you need to understand before you start writing virtual devices (vdevs) for a QNX hypervisor system.
    - Prerequisites
      Before you write your own vdev you should understand what a vdev is so that you know what it is you are writing.
    - Designing a vdev
      Before you begin writing a vdev, you should decide what you need the vdev to do.
    - Integrating a vdev
      After you have written the code for your vdev, you must add it to your hypervisor system.
    - Lifecycle of a vdev
      Here is an overview of the lifecycle of a vdev, from initialization to termination.
    - Guest memory regions
      Use the functions defined in gasp.h to work with memory regions in the guest's physical address space.
    - Reading and writing in a vdev
      When a guest reads from or writes to a vdev, the vdev must perform actions analogous to the actions that hardware performs in response to reads and writes.
    - Terminating qvm process instances and guests
      The method you use in your vdev to terminate a qvm process instance (and, hence, any running guest) depends on the status of the guest.
    - Debugging a vdev
      You can use the same techniques to debug a vdev as you use to debug other code in a QNX OS system.
  - The Basics: vdev trace
    This simple vdev illustrates how to implement basic vdev functionality.
  - Advanced Topics
    This chapter presents examples of more advanced vdevs implemented with QNX hypervisors.
- Virtual Device Developer's API Reference
  The Virtual Device Developer's API Reference presents the QNX hypervisor public virtual device (vdev) API. It is intended for use by developers writing virtual devices (vdevs) in a QNX hypervisor system.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

Prerequisites

Before you write your own vdev you should understand what a vdev is so that you know what it is you are writing.

QNX hypervisor systems and vdevs

We recommend that you do at least the following, in this order:

Read and understand the chapter Understanding QNX Virtual Environments in the User's Guide. You may also find the chapter Performance Tuning useful.
Install and run a QNX hypervisor system, familiarize yourself with the vdevs available, and learn to configure them.
Read and understand this chapter.
Get the source code for the vdevs described in this guide and play with the sample vdevs. The source code is available on GitLab at https://gitlab.com/qnx/hypervisor.

Hardware, QNX OS and other OSs, device drivers, and the VIRTIO standard

We assume that in addition to reading the above-named chapters in the User's Guide and this chapter, and familiarizing yourself with the QNX hypervisor variant that you're using, you know:

the QNX OS, and how to write shared objects for a system built on this OS
your hardware platform; you will be writing software that runs on this hardware and emulates a device on this hardware, so knowing the hardware architecture and the specific board your vdev will run on is essential
the OSs that you will be running as guests in hypervisor VMs, and how to write device drivers for them
the VIRTIO standard, if you will be writing para-virtualized devices based on this standard

Page updated: March 14, 2026