1. Mac OS X thread APIs Mach threads POSIX threads (pthreads)
Cocoa threads (NSThreads)
Carbon Multiprocessing tasks (MP tasks)
Carbon Thread Manager cooperative threads

2. A simple example of the Mac OS X thread layering hierarchy2 1

3. Layered System Architecture
Layers depend on the one located directly below it
Fundamental layers are located towards bottom
Some layers such as Classic, BSD, and QuickTime can interact on a multitude of layers

4. Layered System Architecture Cont.
Compatibility Layers- Classic, BSD
Development Layers- Carbon, Cocoa, Java
Application Layer- Quartz, QuickDraw
Core Layer- Basic Libraries (Strings, Flow Structures, Threads)
Kernel Layer- Mach, BSD, Device Drivers, Networking, File Systems

5. Graphical User Interface: Aqua
Runs on top of Quartz
Full of eye candy, “translucent gel feel”
Dialogs can be attached to a window
                                                              
                                    
                                                   

6. Hardware Platforms iBook, Powerbook, iMac, PowerMac
Motorola’s G3 and G4 CPU’s
Support USB, Firewire, Airport, and Velocity Engine
Downloadable source, DARWIN, can be compiled and run on Intel machines

7. Memory Management Virtual Addressing Demand Paging Preemptive Swapping
Mapping
Memory Protection

8. Directory Structure Root Directory Administrator Account
Three File Types
Plain Files
Directory Files
Device Files
Block
Character