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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
System Analysis Toolkit (SAT) User's Guide
Events and the Kernel
Classes and events
Control class: _NTO_TRACE_CONTROL
The _NTO_TRACE_CONTROL class includes events related to the control of tracing itself.

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
  - 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
  - QNX Filesystem for Safety User's Guide
  - SMMUMAN User's Guide
  - System Analysis Toolkit (SAT) User's Guide
    - Introduction to the System Analysis Toolkit (SAT)
    - Events and the Kernel
      - Generating events: a typical scenario
      - Simple and combine events
      - Fast and wide modes
      - Classes and events
        Communication class: _NTO_TRACE_COMM
        The _NTO_TRACE_COMM class includes events related to communication.
        Control class: _NTO_TRACE_CONTROL
        The _NTO_TRACE_CONTROL class includes events related to the control of tracing itself.
        Interrupt class: _NTO_TRACE_INT
        The _NTO_TRACE_INT class includes events related to interrupts.
        Kernel-call classes: _NTO_TRACE_KERCALLENTER, _NTO_TRACE_KERCALLEXIT, and _NTO_TRACE_KERCALLINT
        These classes track kernel calls.
        Process class: _NTO_TRACE_PROCESS
        The _NTO_TRACE_PROCESS class includes events related to the creation and destruction of processes.
        Security class: _NTO_TRACE_SEC
        The _NTO_TRACE_SEC class includes events related to security.
        System class: _NTO_TRACE_SYSTEM
        The _NTO_TRACE_SYSTEM class includes events related to the system as a whole.
        Thread class: _NTO_TRACE_THREAD
        The _NTO_TRACE_THREAD class includes events related to state changes for threads.
        User class: _NTO_TRACE_USER
        The _NTO_TRACE_USER class includes custom events that your program creates.
    - Kernel Buffer Management
      As the instrumented kernel intercepts events, it stores them in a ring of buffers.
    - Capturing Trace Data
    - Filtering
    - Interpreting Trace Data
      Once the data has been captured, you may process it, either in real time or offline.
    - Tutorials: Controlling event tracing
    - Current Trace Events and Data
  - 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.

Control class: _NTO_TRACE_CONTROL

QNX SDP8.0System Analysis Toolkit (SAT) User's GuideUser

The _NTO_TRACE_CONTROL class includes events related to the control of tracing itself.


Event	traceprinter label	IDE label	Emitted when:
_NTO_TRACE_CONTROLBUFFER	`BUFFER`	`Buffer`	The instrumented kernel starts filling a new buffer
_NTO_TRACE_CONTROLBUFFEREND	`BUFFER_END`	`BufferEnd`	The buffer ends
_NTO_TRACE_CONTROLDROPPED	`DROPPED`	`BufferDropped`	The kernel drops events while waiting for the buffer to become free
_NTO_TRACE_CONTROLTIME	`TIME`	`Time`	The 32 Least Significant Bits (LSB) part of the 64-bit clock rolls over, or the kernel emits an _NTO_TRACE_CONTROLBUFFER event

The purpose of emitting _NTO_TRACE_CONTROLBUFFER events is to help tracelogger and the IDE track the buffers and determine if any buffers have been dropped. The instrumented kernel emits an _NTO_TRACE_CONTROLTIME event at the same time to keep the IDE in sync (in case a dropped buffer contained an _NTO_TRACE_CONTROLTIME event for a rollover of the clock).

Page updated: August 11, 2025