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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.
Graphics
Screen DDK Guide
The Screen DDK (driver development kit) empowers you to support your own hardware (GPUs, display controller, etc), allowing you to write drivers that map their unique hardware capabilities to the standard Screen APIs.
The libscrmem library
Opening Screen memory handles (scrmem_open.h)
scrmem_open()
Obtain a handle to Screen buffer memory

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
  - 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).
  - OpenWF Display Server User's Guide
    The OpenWF Display Server (wfd-server) is a resource manager that provides applications the ability to show image buffers directly to the display controller via the OpenWF Display API.
  - Screen DDK Guide
    The Screen DDK (driver development kit) empowers you to support your own hardware (GPUs, display controller, etc), allowing you to write drivers that map their unique hardware capabilities to the standard Screen APIs.
    - Allocation module
    - Blit module
    - GPU module
    - The libmemobj library
    - The libscrmem library
      - Using Screen memory handles (scrmem.h)
      - Opening Screen memory handles (scrmem_open.h)
        scrmem_open()
        Obtain a handle to Screen buffer memory
        scrmem_open_from_win_image()
        Obtain a handle to Screen buffer memory from a win_image_t
      - Creating Screen memory handles (scrmem_create.h)
      - Examples
  - 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.
  - 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.
- 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 software in Amazon Web Services (AWS) and Microsoft Azure (Azure).
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 and QNX Hypervisor for Safety
The QNX Hypervisor and QNX Hypervisor for Safety products allow 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.
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.

scrmem_open()

Obtain a handle to Screen buffer memory

Synopsis:

#include <scrmem/scrmem_open.h>

errno_t scrmem_open(struct scrmem **scrmem_out, int bufid, int accmode, const struct _client_info *client)

Arguments:

scrmem_out: A pointer to a location where this function, if successful, writes a pointer that represents the reference being held.
bufid: The identifier of the buffer to open. In struct win_image (also known as win_image_t), if WIN_IMAGE_FLAG_SCRMEM is set, the fd field contains the identifier.
accmode: The access mode to use. Pass O_RDONLY, O_RDWR, or O_WRONLY (from fcntl.h).
client: A pointer to information about the client requesting access. This is used to validate that the client has the required permissions. If NULL, no extra checks are done. The structure isn't accessed after this function returns, and future permission changes don't affect existing references.

Library:

libscrmem

Description:

The scrmem_open() function obtains a handle to Screen buffer memory. Use scrmem_close() when finished with it. Screen doesn't free the memory before scrmem_close() is used.

This function can only be called by code running within the Screen process.

Returns:

EOK: A handle was stored at *scrmem_out.

EACCES: The specified client was not allowed to access the object.

EINVAL: An invalid parameter value was specified.

ENOENT: The bufid isn't valid.

EPERM: The client is NULL and accmode specified a disallowed access mode.

Page updated: June 11, 2026