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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 the QNX OS 8.0.
OS Components & Operations
Building Embedded Systems
The Building Embedded Systems guide is intended for developers who are developing or building BSPs for QNX OS embedded systems.
OS Images
OS images are files that contains the OS, your executables, and any data files that might be related to your programs.
Combining multiple image files
Combining the IPL, an OS image (IFS) created by mkifs, and a flash filesystem image created by mkefs can be useful or even required.

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.
- Quickstart Guide
- System Architecture
  The System Architecture guide accompanies the QNX OS and is intended for both application developers and end-users.
- OS Components & Operations
  - Boot Optimization Guide
    The Boot Optimization Guide describes techniques you can use to reduce the time from your board's initial power on until you have a fully functional QNX system running on the board.
  - Building Embedded Systems
    The Building Embedded Systems guide is intended for developers who are developing or building BSPs for QNX OS embedded systems.
    - Overview
      QNX systems are built from the QNX OS standard release components, the architecture- and board-specific files provided in QNX BSPs, and customer and third-party components.
    - Working with QNX BSPs
      Before you attempt to write a new BSP or modify an existing one, it is helpful to know how to use a BSP.
    - Initial Program Loaders (IPLs)
      IPLs first set up the minimum environment needed to execute their compiled C code, then find the OS image and load it into memory, and then jump to the QNX startup code.
    - Startup Programs
      The first program to run in a bootable OS image is the startup program; it completes the system configuration, then launches the OS kernel.
    - Kernel Callouts
      Kernel callouts are standalone pieces of code (or code fragments) that the kernel uses to perform hardware-specific functions. These callouts don't need to be statically linked to the kernel.
    - System Page
      The system page contains essential information about the system, including the system page's size, information about the hardware platform (including IRQs and the CPU), the cache size, and the location of kernel callouts in memory.
    - OS Images
      OS images are files that contains the OS, your executables, and any data files that might be related to your programs.
      - Deciding what goes on the target
        Depending on your system requirements, you will need to transfer different combinations of the IPL, OS image and filesystems to your target.
      - Building an OS image
        An OS image is created by a program called mkifs (make image filesystem), which accepts information from two main sources: its command line and a buildfile. You can change the buildfile to configure the OS image.
      - Building a flash filesystem image
        If your application requires a writable filesystem and you have flash memory devices on your embedded system, you can use a QNX OS flash filesystem driver to provide a POSIX-compatible filesystem.
      - Creating a new filesystem on your target
        You can use QNX utilities to create a new filesystem on your target.
      - Combining multiple image files
        Combining the IPL, an OS image (IFS) created by mkifs, and a flash filesystem image created by mkefs can be useful or even required.
    - OS Image Buildfiles
      You can edit OS image buildfiles to configure OS images.
    - IPL Library
      The IPL library contains a set of routines for building a custom IPL.
    - Startup Library
      The startup library contains a rich set of routines ranging from high-level functions called by main() to utility functions for performing specific startup tasks.
    - Debugging QNX Embedded Systems
      The microkernel architecture of QNX OS means that debugging QNX embedded systems can be different from debugging other embedded systems.
    - Sample Buildfiles
      This appendix contains sample buildfiles that you can modify to support your hardware platform and your implementation requirements.
    - Glossary
  - Customizing a BSP
    While QNX provides Board Support Packages (BSPs) for many common platforms and their individual variants, in some cases, you need a BSP for a board that QNX does not provide. If this is the case, you can modify a QNX BSP or develop your own.
  - Device Publishers Developer's Guide
  - High Availability Framework Developer's Guide
  - High-Performance Networking Stack (io-sock) User's Guide
    This guide contains instructions for implementing and using the QNX OS High-Performance Networking Stack and its manager, io-sock.
  - PCI Server User's Guide
  - Performance Tuning User's Guide
  - SMMUMAN User's Guide
  - System Analysis Toolkit (SAT) User's Guide
  - Technotes
  - User's Guide
    The QNX OS User's Guide is intended for all users of a QNX OS system, from system administrators to end users.
- Graphics
- Programming
- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX OS system and developers who want to create a QNX OS resource manager free from vulnerabilities.
- Utilities & Libraries
- Migrating to QNX OS 8.0
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX OS in the Amazon cloud environment.
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 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).
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.

Combining multiple image files

QNX SDP8.0Building Embedded SystemsConfigurationDeveloper

Combining the IPL, an OS image (IFS) created by mkifs, and a flash filesystem image created by mkefs can be useful or even required.

Some boards accept only a single image, so the OS image and any other other images must be combined before they are transfered to the target board.
A single image can simplify manufacturing of systems after they go into production. Copying a single image is simpler, faster, and less susceptible to error than copying multiple images.

Figure 1The IPL, OS image, and flash filesystem combined into a single image. Padding is used to align the different image components with block sizes required by the board.

Combining the images

To enable configurations like the one above, you must create two separate images and combine them. You can use the diskimage utility to create a single, combined image for a partitioned medium, such as a hard drive, SD card, or MMC on your host, then transfer the image to your target (see the diskimage reference and the diskimage configuration file section in the Utilities Reference, and your BSP User's Guide).

The boot image filesystem will be run from RAM to improve performance, and the eXecute In Place (XIP) image filesystem will be run from flash to conserve RAM.

Note:

Each section of your combined image (IPL, IFS, EFS) must begin at a memory page boundary. Typically, this is a 4 KB boundary; see the diagram above.
The IPL code hands execution to the startup code and OS in the first image.

Instead of using diskimage, you can use a hardware flash or EPROM programmer to burn the separate images with appropriate alignment, or other utilities, such as:

Note:

QNX recommends that you use diskimage to combine images.

For another approach to mounting a secondary image filesystem, see the Reloadable Image Filesystems technote.

Restrictions to using XIP

The following restrictions apply to XIP image filesystems:

The board must support XIP.
The IFS must be uncompressed and stored on linearly mapped media.
The IFS may not reside in NOR flash where there is a flash filesystem driver running for that same flash array (because the flash driver will occasionally put the flash in a mode where it can't be read as data).

Page updated: March 05, 2025