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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.
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newgrp
Change to a new group

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.
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- 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.
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    These libraries provide QNX helpers, including helpers that assist with logging, string conversion, and number and type sizes.
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      - netstat
        Show network status
      - /etc/networks
        Network name database
      - newgrp
        Change to a new group
      - nfsd
        NFS v2 & v3 and MOUNT v1 & v3 protocol server
      - nice
        Run a program at an altered priority (POSIX)
      - nl
        Number lines of input (POSIX, toybox)
      - nm
        List symbols from object files (POSIX)
      - nohup
        Run a command that survives the end of its terminal (POSIX, toybox)
      - /etc/nsswitch.conf
        Name-service switch configuration file
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        Generate public and private keys
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        Network Time Protocol (NTP) daemon
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        Set the local time and date by polling NTP servers
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        Monitor the NTP daemon and determine its performance
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    - Commonly Used Environment Variables
    - Selecting the Target System
    - Glossary
  - WPA Control Interface Reference
    This document provides a reference for the Wi-Fi Protected Access (WPA) control interface, which provides a C API for the WPA/IEEE 802.11i protocols in Wi-Fi client stations. Application developers who want to control WPA operations and get associated status and event data should read this reference.
- 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.

newgrp

QNX SDP8.0Utilities ReferenceUtilities

Change to a new group

Syntax:

newgrp [-l|-s] [group]

Runs on:

QNX OS

Options:

-l: (el) Change the environment to what would be expected if the user actually logged in again.
-s: Set the group ID of the parent; don't exec() a login shell.
group: A group name.

Description:

The newgrp utility starts a new shell with a new real and effective group ID. The user remains logged in and the current directory doesn't change, but file access permissions are based on the new real and effective group IDs.

Note:

This utility needs to have the setuid (set user ID) bit set in its permissions. If you use mkefs, mkifs, or mkqnx6fs on a Windows host to include this utility in an image, use the perms attribute to specify its permissions explicitly, and the uid and gid attributes to set the ownership correctly.

If no operands are specified, newgrp changes the group ID back to the group identified in the invoking user's entry in /etc/passwd.

If you don't use the -l option, the environment variables remain unchanged.

Note that the QNX OS doesn't support group passwords. Only the user root may change the group ID to a group that it doesn't belong to.

Files:

/etc/group: Contains information on the group IDs in the system.
/etc/passwd: Contains information on the user IDs in the system.

See the passwd utility's Files section for a brief description of the format of these files.

Page updated: March 05, 2025