Sun's Adam Leventhal has made a disturbing discovery about Apple's version of DTrace, a free/open debugging tool that Leventhal helps to oversee: Apple has deliberately broken DTrace to prevent it from being used to examine the inner workings of iTunes. This is presumably in place to stop people from figuring out how to break iTunes's DRM, and as Leventhal notes, it is completely contrary to the purpose and spirit of debugging tools and open source:
Wow. So Apple is explicitly preventing DTrace from examining or recording data for processes which don't permit tracing. This is antithetical to the notion of systemic tracing, antithetical to the goals of DTrace, and antithetical to the spirit of open source. I'm sure this was inserted under pressure from ISVs, but that makes the pill no easier to swallow. To say that Apple has crippled DTrace on Mac OS X would be a bit alarmist, but they've certainly undermined its efficacy and, in doing do, unintentionally damaged some of its most basic functionality. To users of Mac OS X and of DTrace: Apple has done a service by porting DTrace, but let's convince them to go one step further and port it properly.
To paraphrase Warren Buffet, DRM is the gate to hell: once you enter, you can't leave. Apple, having committed itself to preventing users from using their computers in certain ways, must now take on a further and further-reaching set of restrictions in service of that — locking down APIs, shipping updates that downgrade the software, exposing user privacy, breaking core development tools. No end in sight — not until Apple decides that what you do with your computer is your own business.