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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
Device Publishers Developer's Guide
Device Publishers
Device publishers are hardware-support components that publish information about attached devices. The QNX OS ships the usblauncher_otg publisher for USB-connected devices. This publisher sends information through its embedded resource manager publisher (RMPS) component. Applications use this information to access the content on devices, which allows them to display file information in browsers or to use multimedia services to read and play media files from those devices.
Role of device drivers
Device drivers enable publishers to communicate with attached devices by supporting POSIX system calls such as open() and read(). Publishers issue these system calls to drivers to obtain information about the devices that the drivers manage; they then publish the information to RMPS objects that applications monitor. Using this information, applications can issue RMPS commands to perform actions such as setting the power of a USB hub.

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.
  - 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
    - Device Publishers
      Device publishers are hardware-support components that publish information about attached devices. The QNX OS ships the usblauncher_otg publisher for USB-connected devices. This publisher sends information through its embedded resource manager publisher (RMPS) component. Applications use this information to access the content on devices, which allows them to display file information in browsers or to use multimedia services to read and play media files from those devices.
      - Role of device drivers
        Device drivers enable publishers to communicate with attached devices by supporting POSIX system calls such as open() and read(). Publishers issue these system calls to drivers to obtain information about the devices that the drivers manage; they then publish the information to RMPS objects that applications monitor. Using this information, applications can issue RMPS commands to perform actions such as setting the power of a USB hub.
      - Resource manager publisher (RMPS) object types
        Device publishers write device information to multiple RMPS objects in fixed locations. Applications can monitor these objects to learn of device updates and to retrieve information that enables access to device contents.
      - Plugins
        Plugins are external components that help device publishers provide extra media-related information.
    - The USB Launcher Service
      The USB launcher service (usblauncher_otg) processes USB device attachments and detachments, launches drivers for communicating with devices, and publishes device information through RMPS. The service can also force a re-enumeration of a device, by resetting it or by requesting it to disconnect and change its personality.
  - 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.

Role of device drivers

QNX SDP8.0Device Publishers Developer's GuideAPIArchitecture

Device drivers enable publishers to communicate with attached devices by supporting POSIX system calls such as open() and read(). Publishers issue these system calls to drivers to obtain information about the devices that the drivers manage; they then publish the information to RMPS objects that applications monitor. Using this information, applications can issue RMPS commands to perform actions such as setting the power of a USB hub.

Here is a summary of how the usblauncher_otg publisher typically interacts with the corresponding drivers:


Activity	Action
Driver startup	USB launcher service starts and stops drivers when devices are added or removed.
Driver communication	Drivers create entries in /dev for attached USB devices and manage communication with USB-connected devices: mass storage, DVD, SD Card, etc. The service monitors /dev entries and, when it notices a state change, asks the driver to retrieve device and mount information, which it then publishes through RMPS.^a The service also gets event notifications (e.g., device insertions and removals) from the USB server; it then writes these to RMPS.

Page updated: March 05, 2025

^a The usblauncher_otg service doesn't perform device-specific actions, such as ejecting the disc in a USB optical drive.