OS X/iOS use a 'sandbox' driver that utilizes TrustedBSD MAC infrastructure ( https://developer.apple.com/library/mac/#documentation/Darwin/Reference/KernelIOKi

OS X/iOS use a 'sandbox' driver that utilizes TrustedBSD MAC infrastructure ( https://developer.apple.com/library/mac/#documentation/Darwin/Reference/KernelIOKitFramework/mac_policy_h/index.html https://developer.apple.com/library/mac/#documentation/Darwi... ). Basically, most system calls can be verified against one or more policy modules, and blocked if non-compliant. Not really possible with Windows and its bajillion of syscalls (1000 in win32k alone afair)