Prevents the display from dimming automatically.


#define kIOPMAssertionTypePreventUserIdleDisplaySleep


When asserted and set to level kIOPMAssertionLevelOn, will prevent the display from turning off due to a period of idle user activity. Note that the display may still sleep from other reasons, like a user closing a portable's lid or the machine sleeping. If the display is already off, this assertion does not light up the display. If display needs to be turned on, then consider calling function IOPMAssertionDeclareUserActivity.

While the display is prevented from dimming, the system cannot go into idle sleep.

This assertion does not put the system into Dark Wake.

A caller publish the AssertionType in its assertion properties dictionary. The AssertionType should be a key in the properties dictionary, with a value of a CFNumber containing the kCFNumberIntegerType value kIOPMAssertionLevelOff or kIOPMAssertionLevelOn.

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