Since Lion (I believe), Apple have folded the "Restart automatically if the computer freezes" functionality into the "Energy Saver" settings of the main OS. Before that, IIRC, it used to be available only in the Server version of the OS, where it was controlled by a daemon called "watchdogtimerd". My understanding of watchdogtimerd is that it would periodically reset a hardware countdown timer in the power supply hardware. If the timer got down to 0, the machine would restart. So a frozen system would get rebooted within a certain time period. Fast-forward to Lion, and we have the "Energy Saver" settings, or "systemsetup -setrestartfreeze", enabling or disabling very similar functionality. But what are the nuts and bolts of how this works? Presumably it still has the same underpinnings of a h/w countdown timer that will restart the machine if it isn't continually reset. But what is doing that - some other "launchd" daemon, or some new code in the kernel? And how does "Energy Saver" or "systemsetup" activate or deactivate that functionality? Any insight on this is appreciated. Thanks! -- Jonathan _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app... This email sent to site_archiver@lists.apple.com