Function IODeregisterForSystemPower 

pub unsafe extern "C-unwind" fn IODeregisterForSystemPower(
    notifier: *mut io_object_t,
) -> IOReturn

Available on crate features libc and pwr_mgt only.

Disconnects the caller from the Root Power Domain IOService after receiving system power state change notifications. (Caller must also destroy the IONotificationPortRef returned from IORegisterForSystemPower.)

Parameter notifier: The object returned from IORegisterForSystemPower.

Returns: Returns kIOReturnSuccess or an error condition if request failed.

Safety

notifier must be a valid pointer.