Understanding the Neutrino Source Tree#
The Neutrino source tree is laid out in a hierarchal manner that quickly itemizes what a source's role in life is. The root of the tree contains broad source categories as it's top level directories:
- These are all of the main operating system services that run on a Neutrino system. An system service is a background process, often a Neutrino resource manager, that provides functionality to other applications via a message passing interface. In addition to services like pipe and mqueue, this is where you will find the Neutrino Kernel/Process Manager in services/system.
- This directory contains the supporting libraries for the operating system. These libraries, both shared and dynamic, provide functionality that is common and shared among many applications. This is where you will find the C and C++ libraries (lib/c and lib/cpp), math and compression libraries (lib/m, lib/z, lib/ucl) and utility libraries (lib/qnx4, lib/compat).
- This directory contains all of the operating system utilties. Utilities differ from services in that they are clients of system services and generally don't provide an API for other programs to access their data directly. The utilities tree is further split with directories a-z to facilitate navigation. For example the ls utility would be found in utils/l/ls while cat would be in utils/c/cat.
- This is home for most of the low level hardware, bit banging, drivers. The frameworks that these drivers fit into are generally located in the lib or services tree, but the hardware drivers for networking, block, serial, usb, graphics and others all live in this section of the source tree. This is also where you will find the home of the different BSP content (hardware/boards)
- Sample applications, many of these based on the Photon windowing system, live here. You will find programs like the Photon File Manager (apps/pfm) as well as
- Ported applications that are not necessarily maintained as part of the standard operating system distribution are included in this directory. These are often open-source projects that have been ported to Neutrino and are of general use. When an open source project is ported then the preference is always to work with the project to integrate the changes required to cleanly build and run the application on Neutrino.