In an apparent attempt to stop developers porting Mac OS X to non-Macs based on Intel processors, Apple has restricted developer access to key elements of its source code.

'With the release of Mac OS X for x86 processors, Apple has chosen not to release source to key components of the OS, such as the kernel and all drivers," said Rob Braun in Dæmon News.

"This means Darwin/x86 is dead in the water; Darwin/ppc has many closed source components and is a deprecated architecture," he added.

In a February 17 comment on Apple's own developer lists, developer Peter O'Gorman explained that he had been looking for specific code which had previously been made available – and suddenly it was gone. "I was amazed," he wrote.

"I assume that the idea is to limit the source code availability to those who are attempting to steal Mac OS X and use it on systems not built or approved by Apple. I can understand and applaud the goal, but not the methods," he added.

The developer then notes a number of software projects that will no longer be able to continue, and argues that Apple's actions effectively undermine the fair play nature of open-source development.

"While many (open source) project's licences do not require that changes be sent back or source code published, I think it only fair play."

Braun is more critical: "One has to wonder why Apple even bothers to release non-GPL'd source at all, if it is unwilling to co-operate with external developers to increase their return on investment and accept external bug fixes and features. Even worse, one has to wonder why people would want to donate their time to such a fruitless and pointless cause."