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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
Options and Qualifiers
Object and attribute qualifiers
PPS supports qualifiers to objects and their attributes.

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.
    - 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
      - Pathname open options
        PPS objects support an extended syntax on the pathnames used to open them.
      - Object and attribute qualifiers
        PPS supports qualifiers to objects and their attributes.
        Nonpersistence qualifier
        You can use the nonpersistence (n) qualifier for objects and attributes. It's very useful for attributes that may not be valid across a system restart and don't need to be saved.
        Item qualifier
        You can use the item (i) qualifier only for attributes. It causes PPS to treat the value following the qualifier as a set of items.
      - Reading and writing from the command line
        You can use standard command-line utilities to view the status of objects or to change their attributes.
      - Access Control List configuration file
        The -A option for the pps command specifies the path to an Access Control List (ACL) configuration file, which can be used to set access permissions. Using the ACL configuration file eliminates reads to establish PPS object access permissions at startup, and can thus be used to reduce startup times.
    - 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 and attribute qualifiers

PPS supports qualifiers to objects and their attributes.

Object and attribute qualifiers are contained in square brackets ([qualifier]) and are prefixed to lines containing an object or an attribute name. The following qualifiers are supported:

n: Nonpersistence. If you set it on an object, the object becomes nonpersistent. If you set it on an attribute, the attribute becomes nonpersistent if the parent object is persistent; otherwise the qualifier is ignored. For more information, see Nonpersistence qualifier.
i: Item. Specifies an item for a set attribute. For more information, see Item qualifier.

Note:

By default, qualifiers aren't set.
On a read() call, you will see a preceding qualifier list [option letters] only for options that have been set.
Attribute options always precede both the special character and the object or attribute name.

If nothing precedes a qualifier, that qualifier is set. It the qualifier is preceded by a minus sign (-), that qualifier is cleared. If a qualifier isn't specified, that qualifier isn't changed. For example:


To:	Specify:
Set the nonpersistence qualifier on an attribute	`[n]url::www.qnx.com`
Clear the nonpersistence qualifier on an attribute	`[-n]url::www.qnx.com`
Leave the current nonpersistence qualifier unchanged	`url::www.qnx.com`
Add `hammer` to a set	`[i]toolbox::hammer,`
Remove `screwdriver` from a set	`[-i]toolbox::screwdriver,`

Page updated: March 12, 2026