Datasheet

Cocoa

Cocoa applications are specifically developed for Mac OS X. Cocoa applications are incompatible

with older Macintosh operating systems and, therefore, do not run on Mac OS 9. Cocoa applications

take advantage of all of Mac OS X’s modern OS features, such as advance memory management,

preemptive multitasking, symmetric multiprocessing, and the Aqua interface. Apple evangelizes

Cocoa for its modern object-oriented programming techniques and rapid application development

tools, which make application development significantly faster and easier than for Carbon. Some

examples of Cocoa applications are OS X’s Mail and Preview applications as well as Netopia’s

Timbuktu for Mac OS X.

Carbon

The greatest advantage of the Carbon application environment is that developers can build applica-

tions that run in either Mac OS 9 or OS X. When running within OS X, Carbon applications take

advantage of most of OS X’s modern OS features, including the Aqua interface. In order for Carbon

applications to run within Mac OS 9, the CarbonLib library must be present within the Extensions

folder within the Mac OS 9 System folder. Ironically, some Carbon applications do not run under

Mac OS 9. The most prominent is Microsoft’s Office Version X for Mac.

Java

The Mac OS X Java environment is Java 2 Standard Edition-compliant. It can run both Java appli-

cations and applets. The key advantage of Java development is that Java applications can run on

any platform that contains a cross-compatible Java Virtual Machine.

BSD

The BSD application environment usually deals with command-line executable shell scripts. A

shell script is similar to an MS-DOS batch file in that they’re both text files that contain a sequence

of commands. Interestingly enough, shell scripts do not necessarily have to be executed from the

command line. Shell scripts can be implemented within Cocoa applications, allowing them to be

executed from the GUI.

Packages and bundles

A package, sometimes referred to as a bundle, is a single-icon, point-and-click representation of an

application. Mac OS X’s Carbon and Cocoa applications can be comprised of multiple subordinate

files and resources. In the GUI, all of these subordinate pieces are neatly wrapped up into a repre-

sentation of a single executable file for the end user. To view the contents of an application package,

simply press and hold the Control key while highlighting the Carbon or Cocoa application icon.

You’re then provided the option to show the package’s contents. For illustration purposes, Figure 1.1

depicts the contents of Safari for Mac OS X.

Frameworks

Mac OS X frameworks contain dynamically loading code shared by multiple applications.

Frameworks alleviate the need for applications that contain common code to individually load that

code for each instance of those applications running simultaneously.

Introduction and Installation of Mac OS X

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