Mac OS: Difference between revisions

▲At the 2005 WWDC, Apple dropped a bombshell on the Mac community: The Mac was moving to the 80x86 family of processors (specifically the Intel Pentium M and Core architectures), effectively making the Mac a PC clone. The main reason stated was that Apple could not get IBM and <s>Motorola</s>Freescale to cooperate on developing a low-power version of the PowerPC G5 CPU, forcing Apple to continue using the aging G4 CPU instead in the highly popular PowerBook and iBook ranges. The G5 itself was infamously power-hungry, with many of the faster models requiring water cooling, and that meant more heat and more fan noise. This was especially irksome to Apple, as the earlier PPC G3 was one of the most efficient CPUs ever made, allowing Apple's laptops to easily hold the title of "World's Fastest" for years. Amusingly enough, Apple's abandonment of the PPC occurred just before the entire 7th generation of [[Videogame Systems]] unanimously switched to it, coinciding with enormous upgrades to the PPC architecture.

▲This was met with some concern from some longtime Mac users, especially after years of Apple advertising touting the RISC-based PPC CPUs over the "snail-like" 80x86 family, but by then times had changed, and most of the standard PC's warts had long since been wallpapered over (by fusing the CISC x86 instruction set with a simple RISC architecture inside the "CRISC" CPU) or had been filled in by new [[Application Programming Interface|APIs]] such as ACPI. Moreover, Apple's own machines had slowly been absorbing technologies from mainstream PCs, such as PCI, ATA, and USB, since the mid 1990s. Finally, OS X's UNIX base made it so that changes on the underlying hardware would not severely impact the user experience, though processor-specific code (usually for math-related things like Photoshop filters) would need to be tweaked or rewritten. Much like the old Mac OS did during the 68k-to-PPC transition, OS X supported "fat binaries", with code for more than one processor type inside. Apple labeled applications using this trick as "Universal binaries," and added options in their developer tools to build for both x86 and PowerPC at the same time. An Intel version of OS X 10.4 was first offered on new Macs immediately after the transition; 10.5 was the first standalone PowerPC/Intel version of the OS available in stores. In 2009, Apple announced that PowerPC processors would not be supported for 10.6, making the break final. Mac OS 10.6 was also granted a license by the Open Group, certifying full compliance with the Single UNIX Specification, which means that Mac OS is now officially a version of UNIX.

▲Things were somewhat harder on developers, though; quite a bit of older Mac OS code had been written with outside or outdated tools (such as Macintosh tools like Think, CodeWarrior, and Apple's MPW or PB; or non-Mac tools like Microsoft Visual Studio) for the Carbon API. The most common, easiest way to write 80x86 programs for OS X is with Apple's Xcode IDE—this is part of what held up Universal releases of popular apps like Adobe Creative Suite and Microsoft Office until 2007-2008. The impact was not significant on developers that had already moved to Xcode, and applications built there were some of the first to go Universal. With the coming of 10.6 and 64-bit applications in common use, Carbon support under OS X is being phased out in lieu of Cocoa (Objective-C natively, bindings for many other languages exist) which means that developers of legacy Mac apps will often need to rewrite their user interface for Cocoa.