LinuxHPC.org/Cluster Builder 1.3

Mac OS X

Mac OS X (officially pronounced "Mac OS Ten") is a line of proprietary, graphical operating systems developed, sold, and marketed by Apple Computer, the latest of which is included with all currently shipping Apple Macintosh computers. Mac OS X is the successor to the original Mac OS, which had been Apple's primary operating system since 1984. Unlike its predecessor, Mac OS X is a multi-user, pre-emptively multitasking, Unix-like operating system built on technology that had been developed at NeXT through the second half of the 1980s and up until Apple Computer purchased the company in early 1997. The operating system was first released in 1999 as Mac OS X Server 1.0, with a desktop-oriented version (Mac OS X v10.0) following in March, 2001.

The server edition, Mac OS X Server, is architecturally identical to its desktop counterpart but usually runs on Apple's line of Macintosh server hardware. Mac OS X Server includes workgroup management and administration software tools that provide simplified access to key network services, including a mail server, a Samba server, a directory server, and a domain name server.

Description

Mac OS X was a radical departure from previous Macintosh operating systems as its underlying code base is completely different from previous versions. Its core, named Darwin, is an open source, Unix-like operating system, built around the XNU kernel with standard Unix facilities available from the command line interface. On top of this core, Apple designed and developed a number of proprietary closed source components, including the Aqua user interface and the Finder shell.

Mac OS X included a number of features intended to make the operating system more stable and reliable than Apple's previous operating systems. Pre-emptive multitasking and memory protection, for example, improved the ability of the operating system to run multiple applications simultaneously without their interrupting or corrupting each other. Many aspects of Mac OS X's architecture are derived from OPENSTEP, which was designed with portability in mind, thus easing the transition from one platform to another. (For example, NEXTSTEP was ported from the original 68k-based NeXT workstations to PA-RISC/SPARC/x86-based machines before NeXT was purchased by Apple, and OPENSTEP was subsequently ported to the PowerPC architecture as part of Apple's Rhapsody project.)

The most visible change was the Aqua graphical user interface. The use of soft edges, translucent colors, and pinstripes (similar to the hardware of the first iMacs), brought more color and texture to the windows and controls on the Desktop than OS 9's "Platinum" appearance had offered. Some, including numerous users of the older versions of the operating system, decried the new look as "cutesy"[3][4] and lacking in professional polish. Others, however, hailed Aqua as being a bold and innovative step forward in a time when user interfaces were seen as being "dull and boring"[5]. Despite the controversy, the look was instantly recognizable, and even before the first version of Mac OS X was released, third-party developers started producing skins for customizable applications, like Winamp, similar to the Aqua appearance. (To some extent, Apple has used the successful transition to this new design as leverage, at various times threatening legal action against people who make or distribute software with an interface the company claims is derived from its copyrighted design[6].)

Mac OS X includes its own software development tools, most prominently an integrated development environment called Xcode. Xcode provides interfaces to compilers that support several programming languages including C, C++, Objective-C, and Java. It supports the ability to target both platforms for which Mac OS X is sold, allowing an application to be built to run only on PowerPC, only on x86, or on both processors as a Universal Binary.

Compatibility

PowerPC

PowerPC versions of Mac OS X retain compatibility with older Mac OS applications by providing an emulation environment called Classic, which allows users to run Mac OS 9 as a process within Mac OS X, so that most older applications run as they would under the older operating system. In addition, the Carbon APIs for Mac OS 9 and Mac OS X were created to permit code to be written to run natively on both systems. The OpenStep APIs are still available, but Apple now calls the technology Cocoa. (This heritage is visible in the Cocoa APIs, in which the class names mostly begin with "NS" for NEXTSTEP.) A fourth option for developers is to write applications in the Java platform, which Mac OS X has supported as a "first class citizen"—in practice this means that Java applications fit as neatly into the operating system as possible while still being "cross-platform", and that GUIs, although being written in Swing, look almost exactly like native Cocoa interfaces. Traditionally, Cocoa programs have been mostly written in Objective-C, with Java as an alternative. However, on July 11, 2005, Apple announced that "features added to Cocoa in Mac OS X versions later than 10.4 will not be added to the Cocoa-Java programming interface." [7]

Mac OS X can run many BSD or Linux software packages, as long as they have been compiled for the platform. Compiled binaries are normally distributed as Mac OS X packages, but some may require command-line configuration or compilation. Projects such as Fink and DarwinPorts provide precompiled or preformatted packages for many standard packages. Since version 10.3, Mac OS X has included X11.app, the company's version of the X11 graphical interface for Unix applications, as an optional component during installation. Apple's implementation is based on XFree86 4.3 and X11R6.6, with a window manager which mimics the Mac OS X look, closer integration with Mac OS X, and extensions to use the native Quartz rendering system and to accelerate OpenGL. Earlier versions of Mac OS X can run X11 applications using XDarwin.

For the early releases of Mac OS X, the standard hardware platform supported was the full line of Macintosh computers (laptop, desktop, or server) based on PowerPC G3, G4, and G5 processors. Later versions of Mac OS X discontinued support for some older hardware; for example, Panther does not support "beige" G3s, and Tiger does not support systems that pre-date Apple's introduction of FireWire ports. However, a patch can be applied to the installation disc, or free tools such as XPostFacto have enabled installation of versions of Mac OS X on certain older systems not officially supported by Apple, including some pre-G3 systems. Except for features requiring specific hardware (e.g. graphics acceleration, DVD writing), the operating system offers the same functionality on all supported hardware.

Features

Uses a subset of the Portable Document Format (PDF) as the basis of its imaging model, named Quartz.
Full-color, continuously-scalable icons.
Drop shadows around window and isolated text elements to provide a sense of depth.
Global application services - spell checker, special characters palette, color picker, font chooser and dictionary.
Anti-aliasing of widgets, text, graphics and window elements.
New interface elements including sheets (document modal dialogs attached to specific windows) and drawers.
Interweaving windows of different applications (not necessarily adjacent in the visible stacking order).
ColorSync color matching built into the core drawing engine (for print and multimedia professionals).
OpenGL composites windows onto the screen to allow hardware accelerated drawing. This technology (introduced in version 10.2) is called Quartz Extreme.
Exposé (introduced in version 10.3) Instantly display all open windows as thumbnails for easy navigation to different tasks, display all open windows as thumbnails from the current application, and hide all windows to access the desktop.
Pervasive use of Unicode throughout the operating system.
Straightforward architecture for localization of applications and other code, fully separating language dependencies from the core code of a program.
FileVault (introduced in version 10.3) encrypts the user's Home folder with Advanced Encryption Standard (AES) 128-bit keys.
Dashboard (introduced in version 10.4) supports small applications ("widgets") that can be called up and dismissed in one keystroke.
Spotlight search technology (introduced in version 10.4) allows rapid real-time searches of data files, mail messages, photos, and other information, based on item properties (meta data) and/or content.
Automator (introduced in version 10.4) an application designed to create an automatic work-flow for different tasks.
Smart Folders (introduced in version 10.4) allow for dynamically updated folders depending on a set criteria.
A well defined set of Human Interface Guidelines followed by almost all applications giving them intuitive, consistent user interface and keyboard shortcuts.
Xgrid allows networked Macs to form a distributed computing system.
Built in virtual file system images .dmg supporting encryption and compression, and optionally read/write capability.
Integrated Sync Services (introduced in version 10.4) allows applications to access a centralized extensible database for various elements of user data, including calendar and contact items. The operating system manages conflicting edits and data consistency.

Pricing

Mac OS X comes included in the price for new Macs. Minor upgrades are free and can be downloaded using Software Update. Major upgrades cost US$129 (CAD$149) from Apple. There is also a US$199 (CAD$249) "Family Pack" version of Mac OS X that comes with 5 licenses for home users who have more than one Mac at home. Developers can register for free with the Apple Developer Connection (ADC) to download developer tools such as Xcode and documentation. ADC also offers several for-pay plans including both shipping and beta versions of Mac OS X. Student and educator pricing on Mac OS X software is roughly 10% to 50% lower than standard retail pricing. The Mac OS X Server 10-client license costs US$499 and an unlimited client license is US$999 as of April 1, 2006.

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available under the GNU Free Documentation License. It uses material from
the Wikipedia article "Mac OS X".}}