If you attempt to use Command-Shift-0 (zero) as a keyboard shortcut within an application program, the system goes to sleep.
Solution
Do not use Command-Shift-0 as a keyboard shortcut. If there is a menu item for the command, use it instead. Alternatively, you may be able to use Command-Shift-0 with the zero key on numeric keypad; some applications recognize this sequence.
Command-Shift-0 is used by Mac OS 9 as a keyboard shortcut to put the system to sleep. The command is intercepted by Mac OS 9 and processed; it is never sent to the application.
Command-Shift-number key sequences are reserved for system use. Prior to Mac OS 9, Command-Shift-0 was used by PowerBook computers as a keyboard shortcut to put the system to sleep. Mac OS 9 brings this feature to desktop Macintosh computers, too. Apple developer documentation has noted the following for many years:
"You shouldn't assign a Command-Shift-number key sequence to a menu item as its keyboard equivalent; Command-Shift-number key sequences are reserved for use as 'FKEY' resources. Command-Shift-number key sequences are not returned to your application, but instead are processed by the Event Manager. The Event Manager invokes the 'FKEY' resource with a resource ID that corresponds to the number that activates it."
This article provides information about a non-Apple product. Apple, Inc. is not responsible for its content. Please contact the vendor for additional information.
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