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Startup Disk Control Panel Application
The Startup Disk control panel application is now scriptable, allowing you to get or set the startup disk as well as the startup system folder on a disk having more than one system folder. It can also be used to determine whether your machine started up from the network (NetBoot) or locally. Unfortunately, as many have reported, Script Editor won't compile any of the Startup Disk application properties, even though it can read the Startup Disk dictionary. Using the raw class codes within chevrons does not cure the problem and doesn't appear to be a workaround. Oddly, at least one third-party editor, Scripter 2.5, will compile and run Startup Disk scripts correctly, although the Localboot property returns no value.