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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
QNX Process Launch and Monitor Service User's Guide
The QNX Process Launch and Monitor Service (QPLMS) user's guide is intended for developers who are implementing the service in a QNX OS-based system.
Configure QPLMS
component
task
Main task statements
rlimits

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
  - QNX Process Launch and Monitor Service User's Guide
    The QNX Process Launch and Monitor Service (QPLMS) user's guide is intended for developers who are implementing the service in a QNX OS-based system.
    - QNX Process Launch and Monitor Service (QPLMS) overview
      QPLMS manages and optimizes process execution by launching dependency-driven components — often in parallel — using an action queue and worker threads to support both automated and user-triggered tasks.
    - Configure QPLMS
    - QPLMS usage differences between QOS 2.2.x and SDP 8.x environments
    - Configuration file changes between QPLMS versions
  - 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.
- 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 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.

rlimits

QNX SDP8.0PLMS User's GuideAPIConfigurationDeveloper

Syntax

rlimits = [rlimit:cur[:max], …]

Description

The rlimits keyword specifies the resource limit for the process to be spawned. The fields include:

rlimit

The definitions include:

AS:size_in_bytes
CORE:size_in_bytes
CPU:CPU_time_in_seconds
DATA:size_in_bytes
FREEMEM:tenths_percent_total_mem
NOCONN:max_connections
NOFILE:max_fd
NPROC:max_processes
NTHR:max_threads
SIGEVENT:max_sigevvents
TIMERS:max_timers
CHANNELS:max_channels (supported in SDP 8.x)
MQUEUE_NUM:max_mqueues (supported in SDP 8.x)
MQUEUE_SIZE:max_queue_size (supported in SDP 8.x)
SHM_HANDLES:max_shmem_handles (supported in SDP 8.x)

cur

The rlim_cur field (i.e., the soft limit). It can be a number or inf for RLIM_INFINITY.

max (optional)

The rlim_max field (i.e., the hard limit). It can also be a number or inf. If you don't specify this limit, it maintains its previous value.

Refer to the QNX SDP documentation on rlimits for more information on how the settings are used.

Default

The process inherits plms limits.

Example

rlimits = ["AS:4096", "TIMERS:100"]

Multiplicity

Zero or one instance in a task block.

Constraints

If rlimits is specified in a task, then the task must have one of the exec*() functions so that rlimits is used at run time.

Page updated: June 11, 2026