Shutdown at specific time, not using Energy Saver

I'm setting up a Mac running OS X 10.8.5 to do the following;

• Start up automatically at a specific time
• Launch a Parallels virtual machine (Windows 7)
• Run a program on Windows to collect data
• Suspend the Parallels virtual machine
• Shut down the Mac

The machine starts up nicely using Energy Saver scheduler as expected.

I'm using custom launchd.plist entries to run the Windows VM and suspend it. This happens without there being a graphical login to the Mac.

I cannot use Energy Saver to schedule a shutdown because there has to be a user logged in for that to work.

At the moment I can't get a launchd.plist to shutdown because Unix security prevents anonymous shutdown.

The log entry is;

Text
1 2	30/10/2013 04:17:08.783 com.apple.launchd[1]: (0x7fe6c0423fa0.anonymous.shutdown[449]) Switching sessions is not allowed in the system Mach bootstrap. 30/10/2013 04:17:08.783 com.apple.launchd[1]: (0x7fe6c0423fa0.anonymous.shutdown[449]) _vprocmgr_switch_to_session(): kr = 0x44c

Does anyone have any suggestions?

OK, false alarm, I seem to have solved this by using the pmset command

I was going to suggest using cron to runn the "shutdown" command, but I haven't tried it.

cron may very well run into the same problems as launchd. I know that in OS X, cron is now frowned upon.

pmset turns out to be ridiculously easy to use and doesn't care whether a user is logged in or not. If a user is logged in they get a popup window allowing them to stop the scheduled shutdown.