macosupgrade
I'm upgrading macOS High Sierra. During upgrading, I close the lid for some time, then open the lid to see if upgrade finished. But when I open the lid, the system continue to upgrade from the progress I left. How does Mac do this?
I mean it needs an operating system to control pause/resume, but the OS is under upgrading, how can it control the computer?
First, make sure that iTunes is signed into the iPad owner's Apple account. It is best if this is done in a separate login account on the computer so you do not loose any of your saved apps and backed up data.
Then from there once you plug it in to a full backup to the computer, no upgrading yet! Always do a full backup before an upgrade. Once backed up go and do the upgrade. This will wipe all data on the iPad! Once the update is installed, it will then restore all the prior apps, data, music, movies, pictures and books the tablet.
After that, everything should be golden.
(This is based on my experience upgrading an iPhone 4 from iOS 4 to 5.)
Open Launchpad and you will see your downloading app. Simply click on the app icon to pause the download, and click it again to resume.
Best Answer
This is managed by the System Management Controller (SMC).
The SMC is basically a chip in Intel-based Macs that manage many of the physical aspects of your Mac. This includes power buttons, LED indicators, cooling fans, how your Mac works in its various sleep modes, and so on.
Because the SMC is a sub-system of your Mac, it is not dependent on an operating system being installed.
You may be interested in reading Reset the System Management Controller (SMC) on your Mac - although there is no reason for you to reset the SMC as it did what it was supposed to do in your case.