DarwinDarwin is the from Apple named operating system core for Mac OS X. Darwin is Mac OS X without the user interface. The BSD Unix and Mach 3.0 based Kernel connects since the first release in 1999 characteristics of the booth worlds Apple and UNIX. Mac OS X has beside the Mac OS predecessor his origin in the know how of NeXT technology, taken over by Apple in 1997. NeXT has developed the OPENSTEP operating system which was the further development of NEXTSTEP which in turn is based on 4.3 BSD. Apple supports actively the BSD community, because Darwin is compatibly with the FreeBSD distribution as a reference and takes advance of much open source projects. Mac OS X merge therefore the efficiency and stability of UNIX (protected memory area) with the simple usability of Mac OS.
Affected by the open source concept developers of Apple and the open source community work together for the PowerPC and x86 operating system version. Modifications and further developments flow back to the public, after a free registration the source code can be downloaded from the Apple web site. It can not be excluded that Darwin with his operating system core xnu splits up into independent distribution. All developed applications for the Darwin system core work also under Mac OS X, except for special Mac OS X applications which do not run directly under Darwin. Standard format for executable applications in Darwin is Mach-O. Support for the primarily by Linux program used .ELF format is not possible at present, but Linux applications can be ported.
ArchitectureBy the related UNIX design Mac OS X profits from the protected memory area and established preemptive multitasking. The Kernel consists of 5 components. Includet are the Mach Mikrokernel with the BSD subsystem, file system, network ability and the I/O Kit. The file system supports file names with up to 255 characters and unicode. The Mach Micro kernel cares about the resource management like processor performance, scheduler, memory protection and the communication between the system layers. The core is enclosed by a specified version of the 4.4 BSD-Lite2 Kernel and userland. This contains POSIX APIs and abstracts the file system and the network communication. The BSD Kernel takes care for the administration of system processes and security policies and threading of program parts for Mac OS X.
The I/O Kit introduced with Darwin is a object-oriented development software which provides the ressources for the development of driver software with the support of SMP and preemptive multitasking.
The project OpenDarwin was founded in 2002 with the goal to provide a development environment for the Mac OS X source code and to develop a Darwin derivat. The new created community is a test platform for bug fixes as well as new functions for Mac Os X and Darwin that Apple integrate into the official source code.
At 2006-07-25 the OpenDarwin team and the administrators announced the termination of this project. For reason the failure of the reaching of the goals was named. The project envolved more to a host for Mac Os X project than to a development platform.
|2000 April||Darwin 1.0, kernel xnu 68.4-1.1|
|2000 Nov.||Darwin 1.2.1|
|2001 April||Darwin 1.3.1|
|2001 Oct.||Darwin 1.4.1, base for Mac OS X 10.1|
|2002 Sept.||Darwin 6.0.1, base for Mac OS X 10.2, compiled with gcc 3.1|
|2003 April||Darwin 6.5, base for Mac OS X 10.2.5, compiled with gcc 3.1|
|2003 Oct.||Darwin 7.0, base for Mac OS X 10.3|
|2004 July||Darwin 7.2.1|
|2005 May||Darwin 8.1, base for Mac OS X 10.4.1|
|2007 Nov.||Darwin 8.11, base for Mac OS X 10.4.11|
|2007 Oct.||Darwin 9.0, base for Mac OS X 10.5|
|2007 Nov.||Darwin 9.1, base for Mac OS X 10.5.1|
|2008 Feb.||Darwin 9.2, base for Mac OS X 10.5.2|