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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.
OS Components & Operations
Persistent Publish/Subscribe Developer's Guide
Objects and Their Attributes
The QNX Neutrino PPS service is a system with objects whose properties a publisher can modify.
Object syntax
In listings of the PPS filesystem, PPS objects have no special identifiers. That is, they will appear just like any other file in a listing. For example, the PPS object "PlayCurrent" in the directory /pps/media will appear in a file listing as simply /pps/media/PlayCurrent.

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
  - Adaptive Partitioning User's Guide
  - 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 Neutrino RTOS embedded systems.
  - Core Networking Stack User's Guide
    This guide introduces you to the QNX Neutrino Core Networking stack and its manager, io-pkt.
  - 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 Neutrino High-Performance Networking Stack and its manager, io-sock.
  - Instant Device Activation
  - Migrating to QNX SDP 7.1
  - PCI Server User's Guide
  - Persistent Publish/Subscribe Developer's Guide
    - QNX Neutrino PPS Service
      The QNX Neutrino Persistent Publish/Subscribe (PPS) service is a small, extensible publish and subscribe service that offers persistence across reboots. It's designed to provide a simple and easy-to-use solution for both publish/subscribe and persistence in embedded systems, answering a need for building loosely connected systems using asynchronous publications and notifications.
    - Objects and Their Attributes
      The QNX Neutrino PPS service is a system with objects whose properties a publisher can modify.
      - Object files
        PPS objects are implemented as files in a special PPS filesystem. By default, PPS objects appear under /pps, but this path depends on the -m option used when you start pps. There's never more than one instance of a PPS object, so changes to that object are immediately visible to subscribers.
      - Change notification
        PPS informs publishers and subscribers when it creates, deletes, or truncates an object.
      - Object syntax
        In listings of the PPS filesystem, PPS objects have no special identifiers. That is, they will appear just like any other file in a listing. For example, the PPS object "PlayCurrent" in the directory /pps/media will appear in a file listing as simply /pps/media/PlayCurrent.
      - Attribute syntax
        PPS objects have user-defined attributes. Attributes are listed in a PPS object after the object name.
    - Persistence
    - Publishing
    - Subscribing
      PPS clients can subscribe to multiple objects, and PPS objects can have multiple subscribers. When a publisher changes an object, all clients subscribed to that object are informed of the change.
    - Options and Qualifiers
    - Server Objects
    - PPS Encoding and Decoding API
      The PPS encoding and decoding API makes it easy to encode and decode complex data structures such as arrays and objects in PPS attributes and to ensure attributes are properly typed.
    - PPS API reference
      This chapter describes the publicly visible PPS API functions and data types.
    - Examples
  - Platform-independent Publish/Subscribe Developer's Guide
    This guide is intended for application developers who want to use the Platform-independent Publish Subscribe (PiPS) framework to exchange information with other applications. First, the overall PiPS design and data-exchange model are explained. Then, tutorials on using PiPS are given. These tutorials cover key tasks such as selecting a publish-subscribe provider to use and writing plugins that read and write custom data types.
  - QDB Developer's Guide
  - QNX Helpers Developer's Guide
    These libraries provide QNX helpers, including helpers that assist with logging, string conversion, and number and type sizes.
  - SMMUMAN User's Guide
  - System Analysis Toolkit (SAT) User's Guide
  - System Architecture
    The System Architecture guide accompanies the QNX Neutrino RTOS and is intended for both application developers and end-users.
  - Technotes
  - User's Guide
    The QNX Neutrino User's Guide is intended for all users of a QNX Neutrino RTOS system, from system administrators to end users.
- Audio & Graphics API
- Multimedia
- Networking Middleware
- Programming
- 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.

Object syntax

In listings of the PPS filesystem, PPS objects have no special identifiers. That is, they will appear just like any other file in a listing. For example, the PPS object "PlayCurrent" in the directory /pps/media will appear in a file listing as simply /pps/media/PlayCurrent.

In the results of a read of a PPS file, the first line identifies the object. This line is prefixed with an "@" character to identify it as the object name. The lines that follow define the object's attributes. These lines have no special prefix.

Suppose the PPS object "PlayCurrent" in the example above contains attributes describing the metadata for the currently playing song in a multimedia application. Let's assume that the attributes have the following format:

@PlayCurrent
author::[Presentation text for track author]
album::[Presentation text for album name]
title::[Presentation text for track title]
duration::[Track duration, floating point number of seconds]
time::[Track position, floating point number of seconds]

An open() call followed by read() call on this file returns the name of the object (the filename, with an "@" prefix), followed by the object's attributes with their values:

@PlayCurrent
author::Beatles
album::Abbey Road
title::Come Together
duration::3.45
time::1.24

Note:

Object names may not contain any of the following: "@" (at sign), "?" (question mark), "/" (forward slash), linefeed (ASCII LF), or ASCII NUL.
Every line in the PPS object is terminated with a linefeed ("\n" in C, or hexadecimal 0A), so you must encode this character in a manner agreed upon by cooperating client applications. That is, any values containing ASCII LF or NUL characters must be encoded. The encoding field can be used to assist cooperating applications in determining what encoding is used in the value field.

Page updated: March 12, 2026