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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.
Programming
Getting Started with the QNX OS
Getting Started with the QNX OS: A Guide for Realtime Programmers is intended to introduce you to the QNX OS and help you develop applications and resource managers for it.
Resource Managers
In this chapter, we'll take a look at what you need to understand in order to write a resource manager. Resource managers are another distintive feature of QNX OS that allow you to access services through standard POSIX calls.
Handler routines
Not all outcalls correspond to client messages—some are synthesized by the kernel, and some by the library.
Connect functions notes
Before we dive into the individual messages, however, it's worth pointing out that the connect functions all have an identical message structure.
Internal use part

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
- Graphics
- Programming
  - Getting Started with the QNX OS
    Getting Started with the QNX OS: A Guide for Realtime Programmers is intended to introduce you to the QNX OS and help you develop applications and resource managers for it.
    - Processes and Threads
      This chapter explains the concepts behind processes and threads, and the challenges of synchronization and scheduling. A thread is a flow of execution, and a process is a collection of threads. In the QNX OS, the schedulable entity is a thread, not a process.
    - Message Passing
      In this chapter, we'll look at the most distinctive feature of QNX OS, message passing. Message passing lies at the heart of the operating system's microkernel architecture, giving the OS its modularity.
    - Interrupts
      In this chapter, we'll take a look at interrupts, how we deal with them under QNX OS, their impact on scheduling and realtime, and some interrupt-management strategies.
    - Resource Managers
      In this chapter, we'll take a look at what you need to understand in order to write a resource manager. Resource managers are another distintive feature of QNX OS that allow you to access services through standard POSIX calls.
      - What is a resource manager?
        A resource manager is simply a program with some well-defined characteristics.
      - The client's view
        We've already seen a hint of what the client expects. It expects a file-descriptor-based interface, using standard POSIX functions.
      - The resource manager's view
        Let's look at things from the resource manager's perspective.
      - The resource manager library
        Before we get too far into all the issues surrounding resource managers, we have to get acquainted with the QNX OS resource manager library.
      - Writing a resource manager
        Now that we've introduced the basics—how the client looks at the world, how the resource manager looks at the world, and an overview of the two cooperating layers in the library, it's time to focus on the details.
      - Handler routines
        Not all outcalls correspond to client messages—some are synthesized by the kernel, and some by the library.
        General notes
        Each handler function gets passed an internal context block (the ctp argument) that should be treated as read-only, except for the iov member.
        Connect functions notes
        Before we dive into the individual messages, however, it's worth pointing out that the connect functions all have an identical message structure.
        Internal use part
        End-user parameter part
      - Alphabetical listing of connect and I/O functions
        This section gives an alphabetical listing of the connect and I/O function entry points that you can fill in (the two tables passed to resmgr_attach()). Remember that if you simply call iofunc_func_init(), all these entries will be filled in with the appropriate defaults; you'd want to modify a particular entry only if you wish to handle that particular message. In the Examples section, below, you'll see some examples of the common functions.
      - Examples
        I'm now going to show you a number of cookbook examples you can cut and paste into your code, to use as a basis for your projects. These aren't complete resource managers—you'll need to add the thread pool and dispatch skeleton shown immediately below, and ensure that your versions of the I/O functions are placed into the I/O functions table after you've done the iofunc_func_init(), in order to override the defaults!
      - Advanced topics
        Now that we've covered the basics of resource managers, it's time to look at some more complicated aspects.
      - Summary
        Writing a resource manager is by far the most complicated task that we've discussed in this book.
    - Sample Programs
      This appendix contains the complete versions of some of the sample programs discussed in this book.
    - Glossary
  - Programmer's Guide
    The QNX OS Programmer's Guide covers a variety of topics that might interest developers who are building applications that will run under the QNX OS.
  - Writing a Resource Manager
- 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.

Internal use part

QNX SDP8.0Getting Started with the QNX OSDeveloperUser

The first part consists of fields that the resource manager library uses to:

determine the type of message sent from the client
validate (ensure that the message is not spoofed)
track access mode (used by helper functions)

To keep things simple, I recommend that you always use the helper functions (the iofunc_*_default() ones) in all connect functions. These will return a pass/fail indication, and after that point, you can then use the End-user parameters members within the connect function.

Page updated: March 05, 2025