To what extent OS X is free?

[lbodnar]

Since it is essentially a BSD-derived open source project it is available for free to anyone from Apple itself.

As OS X user interface and iApps are simply independent tasks - it seems to me that it is possible to keep existing GUI (OS X 10.3) but keep "the foundation" (multitasking/file system/memory mangement/IO) current without "annual maintenance fee".

Or basically if you are a command line or X11 user, then you don't even need to buy anything at all besides hardware?

So the question again, how much of OS X 10.3 retail box is free?

 

[robbieduncan]

The underlying system that Mac OSX runs on is called Darwin and can be downloaded (in source form) for free from Apple. This covers the kernel layer (and the BSD sub-system) but non of the parts that make OSX what it is. You do not get any of Carbon/Cocoa/Quartz for example. Whilst you can boot Darwin and then run X11 (not the version you get from Apple though) and use Unix apps I'm not sure why you would bother. You could just run BSD/Linux. It might be possible to compile newer versions of Darwin and slide them in under older versions of Mac OSX but this would be unsupported and probably very buggy. The advantages of this are not likely to be worth the effort. Almost all of the changes (noticable to a normal user) from 10.2 to 10.3 are in the non-free layers above Darwin.

 

[caveman_uk]

Originally posted by robbieduncan
Almost all of the changes (noticable to a normal user) from 10.2 to 10.3 are in the non-free layers above Darwin.

There were some major changes in the free parts too. More of the Linux APIs are now supported and the underlying BSD is now based on FreeBSD 5 as opposed to 4.x

 

[robbieduncan]

Originally posted by caveman_uk
There were some major changes in the free parts too. More of the Linux APIs are now supported and the underlying BSD is now based on FreeBSD 5 as opposed to 4.x

True but these changes will not be noticed by your average user. The APIs are the standardises POSIX APIs. Linux has an implementation of these but it was not the source of them. The POSIX standard was created before Linux existed to enable easier transfer of programs between Unixes.

 

[lbodnar]

How easy/reasonable is it to recompile the kernel for particular hardware? I don't see a reason to have the same kernel booting on DP G5 and older eMacs. Very few (if any) *nix installations run stock kernel.

I want to try to make it "leaner".