site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com On Nov 29, 2007, at 1:38 PM, Thomas Inskip wrote: Allow me to split a hair here. Resource access control is handled in a number of different ways. It's a uselessly gross oversimplification. Let me ask the usual question: What are you actually trying to do? = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... I am not completely new to the darwin underpinnings, but I have been assigned a task that definitely requires pretty good knowledge of the mach kernel. First I'd like to ask what's a good introduction to the kernel (let's call it a crash course). I hate to say this, but there is no such thing. There's simply no way that you can absorb that much information and background in a 'crash course'. Amit's book is good, and will help you get your feet, but expect to spend months if not years getting comfortable. Next I'd like to explain what I need to be able to do. I basically need to be able to detect when someone is reading from a shared resource (in this case the display buffer). Do you want to know when they *are reading*, or when they are *granted permission to read*? For what I understand, any such resources are arbitrated through mach ports. The framebuffer itself is rarely accessed directly by a client; there are high-level interfaces for obtaining its contents. If a process needs access to one, it obtains either read or write rights to it (multiple reader, single writer?), and then is able to access the resource. Is this correct? If so, I should be able to determine when someone obtains read access to such a port via the kernel trace facility or something similar. At least that's my idea. Perhaps I am wayyyyyyy off. Feel free to let me know if that's so or if I am oversimplifying things. This email sent to site_archiver@lists.apple.com