Home
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.
Audio & Graphics API
Screen Graphics Subsystem Developer's Guide
QNX Screen Graphics Subsystem is a graphics framework that provides all the functionality necessary to develop interactive user experiences.
Utilities and binaries
Screen includes some utilities and binaries to help with calibration, debugging, and demonstrating features.
screen
Start Screen services

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
- Audio & Graphics API
  - Audio Developer's Guide
    The Audio Developer's Guide is intended for developers who want to write audio applications using the QNX Sound Architecture (QSA) drivers and library.
  - Gestures Library Reference
    The Gestures library provides gesture recognizers to detect gestures through touch events that occur when you place one or more fingers on a touch screen.
  - Image Library Reference
  - Input Events Library Reference
    The Input Events library provides the framework necessary for Screen Graphics Subsystem to communicate with your touch driver.
  - OpenWF Configuration Developer's Guide
    If you are integrating a new display, you must configure and provide the parameters of your display based on its specifications via the OpenWF Display Configuration API (Wfdcfg Library).
  - Screen Graphics Subsystem Developer's Guide
    QNX Screen Graphics Subsystem is a graphics framework that provides all the functionality necessary to develop interactive user experiences.
    - Application Development
      The Screen Graphics Subsystem is based on a client/server model where an application is a client that's requesting graphics services from the server (Screen). It includes a composited windowing system as one of these services, which means all application rendering is performed on off-screen buffers, which then can be later used to update the display.
    - Buffers
      A buffer is an area of memory that stores pixel data. Multiple buffers can be associated with a window or stream, but only one buffer can be associated with a pixmap.
    - Rendering
      Rendering refers to the generation of an image.
    - Windowing
      Windows are used to display content and to combine content produced by different renderers. Each of the different renderers can be in the same process, or in another process or processes.
    - Resource Sharing
      Resource sharing allows the access of buffers and their content within the same application and process, or between different applications and processes.
    - Displaying the contents of windows
      Displays are used to show the contents of your windows on physical hardware such as a computer monitor or a touchscreen display.
    - Input
      One key aspect of Screen that enables the development of fully interactive user experiences is the functionality to support input events and to deliver input and notifications back to applications.
    - Event Handling
      Screen events, which include both input and general events, are associated with a given context and are generally handled in your main application's loop.
    - Asynchronous Notifications
      Applications can request to be asynchronously notified of specific Screen events by way of a sigevent.
    - Permissions and Privileges
      Permissions and privileges together determine the level of access to API objects (e.g., windows and sessions).
    - Security policies
      This section on Screen security policies is intended for system integrators who are responsible for implementing and enforcing security policies that create and maintain a trusted execution environment.
    - Utilities and binaries
      Screen includes some utilities and binaries to help with calibration, debugging, and demonstrating features.
      - calib-touch
        Calibrate a touchscreen
      - cl10-pi
        An OpenCL 1.0 based demo for PI number generation with validation
      - cl11-ray
        Display fragment shader based ray tracer rendered content using OpenCL 1.1
      - clinfo
        Display information on OpenCL platforms and devices
      - drm-intel
        Start the DRM Server for Intel graphics hardware
      - drm-probe-displays
        Detect ports and pipelines for Intel graphics hardware
      - drm-virtio
        Start the DRM Server for graphics hardware in a virtualized environment
      - drm-vmwgfx
        Start the DRM Server for graphics hardware to support virtual target environments in VMware
      - egl-configs
        Query and display the number of all supported framebuffer configurations for the specified display
      - events
        Create a window manager connection to Screen and dump the events received as output to the console.
      - gles1-gears
        Display hardware-rendered content using OpenGL ES 1.x
      - gles1-vsync
        Display hardware-rendered content using OpenGL ES 1.x
      - gles2-gears
        Display hardware-rendered content using OpenGL ES 2.x
      - gles2-maze
        Demonstrate how to use texture, as well as vertex and fragment shaders
      - gles2-teapot
        Demonstrate 3D rendering using OpenGL ES 2.x
      - gles3-gears
        Display hardware-rendered content using OpenGL ES 3.x
      - gltracelogger
        Record all OpenGL calls made by the target application
      - gltraceprinter
        A readable print of the trace (log) file generated from gltracelogger
      - mtouch
        The mtouch service starts the resource managers for touch functionality and loads the configuration
      - screen-gles2-tools
        Generate shader binaries
      - screen
        Start Screen services
      - screencmd
        Change properties of Screen objects via the Screen debug interface
      - screeninfo
        Decode contents of binary files in /dev/screen for debugging
      - screenshot
        Capture content from a display
      - sharewin
        Demonstrate content sharing between windows
      - sw-vsync
        Display software-rasterized content
      - vg-tiger
        Display hardware-rendered content using OpenVG
      - vncserv
        Remote framebuffer VNC server
      - Vulkan utilities and binaries
        Screen includes some utilities and binaries to help with calibration, debugging, and demonstrating features of Khronos's Vulkan APIs.
      - win-vsync
        Display software-rasterized content using multiple windows in a hierarchy
    - Debugging
      Debugging graphics isn't easy. Figuring out where the problem is can be challenging because of the many aspects and components when it comes to graphics. The goal of this chapter is to show the tools and techniques that you can use to help with your investigation.
    - Screen library reference
      Two important aspects to note when using Screen are function safety and function execution types.
    - Configuring Screen
      You configure libraries, drivers, and Screen parameters using the configuration file, graphics.conf.
    - Glossary
  - Video Capture Developer's Guide
    The video capture framework provides applications the ability to capture frames from a video input source. These frames can be passed to a graphics component such as Screen for display.
- 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.

screen

Start Screen services

Syntax:

screen -c filename
       [ -u username[,sgid]*] |
            uid:gid[,sgid]*]]

Runs on:

QNX Neutrino

Options:

-c filename

Specify filename as the absolute pathname to the configuration file that Screen will use. For example:

$ screen -c /usr/lib/graphics/platform/graphics.conf

where platform is the name of your target's platform (e.g., imx6x).

Note:

You must specify this -c option. Otherwise, screen won't run.

On your target, all libraries that you specify in the khronos section of your configuration file should reside in the same directory as the configuration file itself.

-u username[,sgid]*] | uid:gid[,sgid]*]

Switch to the specified user after initialization where:

username: a string representing a user where its associated uid and gid are applied when switching users
gid: an integer that represents a group id
sgid: an integer that represents a supplementary group id
uid: an integer that represents a user id

This option makes screen switch from running as root to the specified general user. Running as a general user provides a more secure runtime environment. If there are any unpredictable applications on the system, they won't be able to leverage screen to run undesirable code as a privileged user.

Description:

Run the screen binary from command line to start Screen services. To run screen on your target, run screen from a shell.

Examples:

To start screen with configuration specific for NXP i.MX6 SABRE Smart target:

screen -c /usr/lib/graphics/iMX6/graphics.conf

To start screen as root, but switch to a general user, joe, after initialization:

screen -u joe

Page updated: March 12, 2026