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POReceiving power notifications (especially shutdown) on Mac OSX
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copied!<p>I'm writing an application in C for the Mac (Leopard) that needs to do some work on receipt of power notifications, e.g. sleep, wake-up, shutdown, restart. It runs via <code>launchd</code> as a launchagent on login then begins monitoring for notifications. The code I'm using to do this is as follows:</p> <pre><code>/* ask for power notifications */ static void StartPowerNotification(void) { static io_connect_t rootPort; IONotificationPortRef notificationPort; io_object_t notifier; rootPort = IORegisterForSystemPower(&rootPort, &notificationPort, PowerCallback, &notifier); if (!rootPort) exit (1); CFRunLoopAddSource (CFRunLoopGetCurrent(), IONotificationPortGetRunLoopSource(notificationPort), kCFRunLoopDefaultMode); } /* perform actions on receipt of power notifications */ void PowerCallback (void *rootPort, io_service_t y, natural_t msgType, void *msgArgument) { switch (msgType) { case kIOMessageSystemWillSleep: /* perform sleep actions */ break; case kIOMessageSystemHasPoweredOn: /* perform wakeup actions */ break; case kIOMessageSystemWillRestart: /* perform restart actions */ break; case kIOMessageSystemWillPowerOff: /* perform shutdown actions */ break; } } </code></pre> <p>However, only the top two for sleep and wake (<code>kIOMessageSystemWillSleep</code> and <code>kIOMessageSystemHasPoweredOn</code>) <strong>ever</strong> get called. I never get any notifcations for restart or shutdown (<code>kIOMessageSystemWillRestart</code> and <code>kIOMessageSystemWillPowerOff</code>).</p> <p>Am I doing something wrong? Or is there another API that would give me the restart and shutdown notifications? I'd prefer to keep it as a C program (as thats what I'm familiar with) but am open to any sensible suggestions of alternatives (I've had a look at login/logout hooks but these seem to be deprecated in favour of launchd).</p> <p>Thanks in advance for any help/tips!</p>

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