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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
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.
Working with Filesystems
The QNX OS provides a variety of filesystems, so that you can easily access DOS, Linux, as well as native Power-Safe disks.
Power-Safe filesystem
The Power-Safe filesystem, supported by the fs-qnx6.so shared object, is a reliable disk filesystem that can withstand power failures without losing or corrupting data.

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
  - 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.
    - Getting to Know the OS
      Welcome to the QNX OS!
    - Logging In, Logging Out, and Shutting Down
      QNX OS is a multiuser operating system; it lets multiple users log in and use the system simultaneously, and it protects them from each other through a system of resource ownership and permissions.
    - Managing User Accounts
      This chapter explains how user accounts work, how users can change their password by using the passwd utility, and how system administrators can use the passwd utility and edit account database files to create and maintain users' accounts.
    - Using the Command Line
      Like QNX 4, Unix, and DOS, the QNX OS is based on a command-line interface that you might want or need to use instead of the GUI.
    - Working with Files
      In a QNX OS system, almost everything is a file; devices, data, and even services are all typically represented as files. This lets you work with local and remote resources easily from the command line, or through any program that works with files.
    - Using Editors
      An editor is a utility designed to view and modify files.
    - Configuring Your Environment
      The Building Embedded Systems guide describes what happens when you boot your system, and what you can do to customize it. This chapter describes how you can customize the environment that you get when you log in, and then describes some of the setup you might need to do.
    - Writing Shell Scripts
      Shell scripting, at its most basic, is taking a series of commands you might type at a command line and putting them into a file, so you can reproduce them again at a later date, or run them repeatedly without having to type them over again.
    - Working with Filesystems
      The QNX OS provides a variety of filesystems, so that you can easily access DOS, Linux, as well as native Power-Safe disks.
      - Setting up, starting, and stopping a block filesystem
        When you launch a block device driver (devb-*), it detects the partitions on the block I/O devices. You can then issue mount commands to start the appropriate filesystems for various partitions.
      - Mounting and unmounting filesystems
      - Managing disk quotas
        For the Power-Safe (QNX6) filesystem, you can define disk quotas to limit how many file entries a user or group of users can create and how large these files can grow.
      - Image filesystem
        By an image, we refer to an OS image here, which is a file that contains the OS, your executables, and any data files that might be related to your programs, for use in an embedded system.
      - /dev/shmem RAM filesystem
        QNX OS provides a simple RAM-based filesystem that allows read/write files to be placed under /dev/shmem.
      - Power-Safe filesystem
        The Power-Safe filesystem, supported by the fs-qnx6.so shared object, is a reliable disk filesystem that can withstand power failures without losing or corrupting data.
        Links and inodes
        File data is stored distinctly from its name and can be referenced by more than one name. Each filename, called a link, points to the actual data of the file itself.
        Booting
        The current boot support is for x86 PC partition-table-based (the same base system as current booting) with a BIOS that supports INT13X (LBA).
        Snapshots
        A snapshot is a committed stable view of a Power-Safe filesystem. Each mounted filesystem has one stable snapshot and one working view (in which copy-on-write modifications to the stable snapshot are being made).
      - QNX compressed filesystem
        The QNX compressed filesystem (QCFS) provides a read-only filesystem that supports the compression of files and metadata so that they take up less space.
      - DOS filesystem
        The DOS filesystem provides transparent access to DOS disks, so you can treat DOS filesystems as though they were QNX OS (POSIX) filesystems. This transparency lets processes operate on DOS files without any special knowledge or work on their part.
      - Linux Ext2 filesystem
        The Linux Ext2 filesystem provided in QNX OS provides transparent access to Linux disk partitions.
      - Flash filesystems
        The QNX OS flash filesystem drivers implement a POSIX-compatible filesystem on NOR flash memory devices.
      - NFS filesystem
        The Network File System (NFS) protocol is a TCP/IP application that supports networked filesystems. It provides transparent access to shared filesystems across networks.
      - Universal Disk Format (UDF) filesystem
        The Universal Disk Format (UDF) filesystem provides access to recordable media, such as CD, CD-R, CD-RW, and DVD. It's used for DVD video, but can also be used for backups to CD, and so on.
      - Squash filesystem
        The Squash filesystem provides support for Linux Squash compressed read-only filesystems.
      - Troubleshooting
    - TCP/IP Networking
      The term TCP/IP implies two distinct protocols: TCP and IP. Since these protocols have been used so commonly together, TCP/IP has become a standard terminology in today's Internet. Essentially, TCP/IP refers to network communications where the TCP transport is used to deliver data across IP networks.
    - Backing Up Data
      No matter how reliable your hardware and electrical supply are, or how sure you are that you'll never accidentally erase all your work, it's just common sense to keep backups of your files. Backup strategies differ in ease of use, speed, robustness, and cost.
    - Securing Your System
      Now that more and more computers and other devices are hooked up to insecure networks, security has become a very important issue. The word security can have many meanings, but in a computer context, it generally means preventing unauthorized people from making your computer do things that you don't want it to do.
    - Fine-Tuning Your System
      This chapter describes how you can improve your system's performance.
    - Understanding System Limits
      Resources on a system tend to be finite (alas!), and some are more limited than others. This chapter describes some of the limits on a QNX OS system.
    - Examples
      This appendix includes samples of some of the files described in this guide.
    - Glossary
- 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 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.
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.

Power-Safe filesystem

QNX SDP8.0User's GuideUser

The Power-Safe filesystem, supported by the fs-qnx6.so shared object, is a reliable disk filesystem that can withstand power failures without losing or corrupting data.

Its features include the following:

510-byte (UTF-8) filenames
You can't use the characters 0x00-0x1F, 0x7F, and 0xFF in filenames. In addition, / (0x2F) is the pathname separator, and can't be in a filename component. You can use spaces, but you have to quote them on the command line; you also have to quote any wildcard characters that the shell supports. For more information, see Quoting special characters in Using the Command Line.
copy-on-write (COW) updates that prevent the filesystem from becoming corrupted by a power failure while writing
a snapshot that captures a consistent view of the filesystem

For information about the structure of this filesystem, see Power-Safe filesystem in the Filesystems chapter of the System Architecture guide.

CAUTION:

If the drive doesn't support synchronizing, fs-qnx6.so can't guarantee that the filesystem is power-safe. Before using this filesystem, check to make sure that your device meets the filesystem's requirements. For more information, see Required properties of the device in the entry for fs-qnx6.so in the Utilities Reference.

To create a Power-Safe filesystem, use the mkqnx6fs utility. For example:

mkqnx6fs /dev/hd0t76

You can use the mkqnx6fs options to specify the logical blocksize, endian layout, number of logical blocks, maximum number of inodes (and hence, files), and so on.

Once you've formatted the filesystem, simply mount it. For example:

mount -t qnx6 /dev/hd0t76 /mnt/psfs

By default, the Power-Safe filesystem creates sparse files when growing a file with ftruncate() or when writing at an offset that is beyond the end of a file. The filesystem counts sparse blocks against the total free space, so it isn't possible to overcommit the disk blocks. To maintain compatibility with previous versions of the filesystem prior to QNX Neutrino 7.1, use the nosparse mount option.

For more information about the options for the Power-Safe filesystem, see fs-qnx6.so in the Utilities Reference.

To check the filesystem for consistency (which you aren't likely to need to do), use chkqnx6fs.

Page updated: August 09, 2024