Carbon (API)

Carbon

Developer(s)	Apple Inc.
Operating system	Classic Mac OS, macOS
License	Proprietary
Website	developer.apple.com/carbon/

Carbon is one of Apple Inc.'s C-based application programming interfaces (APIs) for the Macintosh operating system. Carbon provided a good degree of backward compatibility for programs that ran on the now-obsolete Mac OS 8 and 9. Developers could use the Carbon APIs to port their "classic" Mac software to the Mac OS X platform with far less effort than a port to the entirely different Cocoa system, which originated in OPENSTEP.

Carbon was an important part of Apple's strategy for bringing Mac OS X to market, offering a path for quick porting of existing software applications, as well as a means of shipping applications that would run on either Mac OS X or the classic Mac OS. As the market has increasingly moved to the Cocoa-based frameworks, especially after the release of iOS, the need for a porting library was diluted. Apple did not create a 64-bit version of Carbon while updating their other frameworks in the 2007 time-frame, and eventually deprecated the entire API in OS X 10.8, which was released on July 24, 2012.

The original Mac OS used Object Pascal as its primary development platform, and the APIs were heavily based on Pascal's call semantics. Much of the Macintosh Toolbox consisted of procedure calls, passing information back and forth between the API and program using a variety of data structures based on Pascal's variant record concept.

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