About This Guide

This chapter includes:

What you'll find in this guide

The System Architecture guide accompanies the QNX Neutrino realtime OS and is intended for both application developers and end-users.

The guide describes the philosophy of QNX Neutrino and the architecture used to robustly implement the OS. It covers message-passing services, followed by the details of the microkernel, the process manager, resource managers, the Photon microGUI, and other aspects of QNX Neutrino.

Note: Note that certain features of the OS as described in this guide may still be under development for a given release.

For the latest news and information on any QNX product, visit our website (www.qnx.com). You'll find links to many useful areas -- software downloads, featured articles by developers, forums, technical support options, and more.

The following table may help you find information quickly:

To find out about: Go to:
OS design goals; message-passing IPC The Philosophy of QNX Neutrino
System services The QNX Neutrino Microkernel
System event monitoring The Instrumented Microkernel
Working on a system with more than one processor Multicore Processing
Memory management, pathname management, etc. Process Manager
Shared objects Dynamic Linking
Device drivers Resource Managers
Image, RAM, QNX 4, DOS, CD-ROM, Flash, NFS, CIFS, Ext2 filesystems Filesystems
Serial and parallel devices Character I/O
Network subsystem Networking Architecture
Native QNX Neutrino networking Native Networking (Qnet)
TCP/IP implementation TCP/IP Networking
Fault recovery High Availability
Sharing resources among competing processes Adaptive Partitioning
Graphical environment The Photon microGUI
Terms used in QNX documentation Glossary

Typographical conventions

Throughout this manual, we use certain typographical conventions to distinguish technical terms. In general, the conventions we use conform to those found in IEEE POSIX publications. The following table summarizes our conventions:

Reference Example
Code examples if( stream == NULL )
Command options -lR
Commands make
Environment variables PATH
File and pathnames /dev/null
Function names exit()
Keyboard chords Ctrl-Alt-Delete
Keyboard input something you type
Keyboard keys Enter
Program output login:
Programming constants NULL
Programming data types unsigned short
Programming literals 0xFF, "message string"
Variable names stdin
User-interface components Cancel

We use an arrow (-->) in directions for accessing menu items, like this:

You'll find the Other... menu item under Perspective-->Show View.

We use notes, cautions, and warnings to highlight important messages:

Note: Notes point out something important or useful.

Caution: Cautions tell you about commands or procedures that may have unwanted or undesirable side effects.

WARNING: Warnings tell you about commands or procedures that could be dangerous to your files, your hardware, or even yourself.

Note to Windows users

In our documentation, we use a forward slash (/) as a delimiter in all pathnames, including those pointing to Windows files.

We also generally follow POSIX/UNIX filesystem conventions.

Navigation buttons

At the top and bottom of our HTML docs, you'll see some or all of these buttons:

Use this button: To move:
Previous To the previous part of the document.
Contents "Up" in the document:
  • In a prose book, this typically takes you to About This Guide.
  • In a reference book, it takes you to the listing of items that start with a given letter. For example, if you're looking at the docs for abs(), this button takes you to the listing of the functions that start with A.
Keyword index To the keyword index.
Next To the next part of the document.

Technical support

To obtain technical support for any QNX product, visit the Support + Services area on our website (www.qnx.com). You'll find a wide range of support options, including community forums.

Copyright © 1996-2007, QNX Software Systems. All rights reserved.