Mac OS X internals
by Amit Singh · first published 2006
43% recommend52% neutral4% critical
Why HN recommends it
Provides an in-depth look at the internals of Mac OS X and its XNU kernel, covering Mach IPC and the I/O system. Its systems-level detail suits kernel and low-level developers.
Summarised by Claude from recommending comments
This is the eBook version of the printed book.Mac OS X was released in March 2001, but many components, such as Mach and BSD, are considerably older. Understanding the design, implementation, and workings of Mac OS X requires examination of several technologies that differ in their age, origins, philosophies, and roles.Mac OS X Internals: A Systems Approach is the first book that dissects the internals of the system, presenting a detailed picture that grows incrementally as you read. For example, you will learn the roles of the firmware, the bootloader, the Mach and BSD kernel components (incl
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What makes you say nobody knows how OS X actually works? The developer documents aren't a big batch of jokes, they describe how the system works. Also take a look at "Mac OS X Internals" by Amit Singh, there's more about the inner workings of OS X there than you could ever possibly care to know.
on “Ask HN: Why does no one talk about working or interviewing for Apple?” ↗In addition to XPC, there is also Mach IPC that uses the Mach Interface Generator. The best documentation for that is Mac OS X Internals: A Systems Approach, by Amit Singh, particularly Chapter 9. Unfortunately not updated since 2006, so missing GCD and XPC, among other things.
on “Reaching the Mach layer” ↗…https://www.amazon.com/Revolution-Valley-Insanely-Great-Stor... http://basalgangster.macgui.com/RetroMacComputing/The_Long_V... - NeXTSTEP / Mac OS X Debatable about non-C non-Unixy part, but it surely isn't the focus of the whole stack. "Mac OS X Internals: A Systems Approach" https://www.amazon.com/Mac-OS-Internals-Approach-paperback/d... http://www.nextop.de/NeXTstep_3.3_Developer_Documentation/ - Oberon and its derivatives (1992 and 2013 versions,…
…block device driver, which means I'm digging around in kernels. I've found the O'Reilly books on the Linux kernel ("Understanding the Linux Kernel, 3rd ed" and "Linux Device Drivers, 3rd ed") as well as "Mac OS X Internals" by Amit Singh extremely helpful. The latter doesn't only cover the darwin/xnu kernel but also a lot of the OS X user space. All of them are quite technical and can be a bit dry, but they're certainly…
on “Ask HN: Do you understand your operating system?” ↗i was expecting something in more detail if you want a full in depth history on the mac os x and how it evolved, i would check out "mac os x internals: a systems approach" http://www.amazon.com/Mac-OS-Internals-Systems-Approach/dp/0...
on “How Apple created OS X” ↗Jonathan Levin's MOXiL 2nd Edition volume 3 is out and I recommend you get it. 1st edition is still very good and can hold you off until the other volumes are out. Amit Singh has a Mac OS X Internals A Systems Approach that is good we well. There are also various talks at security conferences that detail parts of macOS/iOS.
on “Debugging macOS Kernel Using VirtualBox” ↗…insights into how some UNIXes got built, these books are quite interesting. "The Design and Implementation of the 4.4 BSD Operating System" "The Design and Implementation of the FreeBSD Operating System" "Mac OS X Internals: A Systems Approach" "Solaris Internals: Solaris 10 and OpenSolaris Kernel Architecture" "HP-UX 11i Internals" "IA-64 Linux Kernel: Design and Implementation"
on “The Source History of Cat” ↗…but what many candidates are missing is a firm understanding of applied programming. Some off the cuff general book suggestions: UNIX Network Programming, Application Programming in a UNIX Environment, Mac OS X Internals, Applied Cryptography, The Design and Implementation of The FreeBSD Operating System, Database in Depth. This list is probably incomplete :) - Don't settle for just an internship. Internships at big…
on “$150K and up for Software Devs in Austin” ↗…space drivers. Also many BSD syscalls have been deprecated along the years, including POSIX features like networking stack, now replaced by Objective-C APIs. I would advise spending some time reading "Mac OS X Internals: A Systems Approach" and "Mac OS X and iOS Internals" books, to learn that having everything on kernel space alone, doesn't rewrite the original microkernel code into a huge monolith.
on “Mach kernel” ↗Says someone that never read Apple documentation or iDevice literature regarding system programming on Apple platforms. You can start by reading the Mac OS X Internals, followed by Mac OS X and iOS Internals: To the Apple's Core. Then hop over to Apple's archive, https://developer.apple.com/library/archive/navigation/
on “Krita, OpenGL and Qt” ↗It's old (circa 2006) and really low level, but I loved reading through Mac OS X Internals (http://www.osxbook.com) If it were updated, or a vol2 was released with all the new stuff, I would immediately buy it. It's not going to teach you how to use Finder, but you'll have a great understanding…
on “We need to document macOS” ↗Mac OS X Internals by Singh is one of my favorite books, such a great in depth examination of Mac OS X circa 10.4. I really wish there was an updated version. Edit: I see it's even cited at the end of this article. Truly…
on “Apple’s Darwin OS and XNU Kernel Deep Dive” ↗> Thank you for the links I will take a closer look at XNU. Another great resource regarding XNU and OS-X (although a bit dated now) is the book: Mac OS X Internals A Systems Approach[0] 0 - https://openlibrary.org/books/OL27440934M/Mac_OS_X_Internals
on “Apple announces Foundation Models and Containerization frameworks, etc” ↗…with components from FreeBSD and a C++ API for writing drivers called IOKit. XNU runs on x86_64 and ARM64 for both single processor and multi-processor configurations. I recommend the book "Mac OS X Internals"[1] for a detailed analysis of same. EDIT: In theory, XNU could simultaneously run the existing FreeBSD subsystem alongside Linux and/or MS-Windows ones. In practice, this would be a herculean effort…
on “The FreeBSD Foundation's Laptop Support and Usability Project” ↗…that there's not an equivalent for MacOS? Is it lack of interest? Is it a technical thing? It is a technical thing. The XNU[0] kernel, which underpins macOS and is detailed by the exceptional book "Mac OS X internals"[1], can theoretically run on many x86 and/or ARM machines. However, the issue with running macOS apps via other operating systems is not the OS, but instead are the GUI frameworks expected (i.e., Carbon[2],…
on “Run macOS Software on Linux” ↗