Jonathan Levin is a longtime trainer and consultant focusing on the system and kernel levels of the 'Big Three'--Windows, Linux, and OS X, as well as their mobile derivatives. He is the founder and CTO of Technologeeks.com, a partnership of experts delivering advanced training on systems/kernel programming, debugging, and profiling.

An in-depth look into Mac OS X and iOS kernelsPowering Macs, iPhones, iPads and more, OS X and iOS are becoming ubiquitous. When it comes to documentation, however, much of them are shrouded in mystery. Cocoa and Carbon, the application frameworks, are neatly described, but system programmers find the rest lacking. This indispensable guide illuminates the darkest corners of those systems, starting with an architectural overview, then drilling all the way to the core.Provides you with a top down view of OS X and iOSWalks you through the phases of system startup--both Mac (EFi) and mobile (iBoot)Explains how processes, threads, virtual memory, and filesystems are maintainedCovers the security architectureReviews the internal Apis used by the system--BSD and MachDissects the kernel, XNU, into its sub components: Mach, the BSD Layer, and I/o kit, and explains each in detailExplains the inner workings of device driversFrom architecture to implementation, this book is essential reading if you want to get serious about the internal workings of Mac OS X and iOS.