How do I know if an update requires restart in macOS Sierra? How do I know if an update requires restart in macOS Sierra? I just updated iTunes and read the description of the update, but couldn't find any mention of a restart required. After a moment the computer restarted without a warning. Luckily, I wasn't in the middle of anything important, but I'd like to avoid such forced restarts in the future.

Edit: There was also a macOS Sierra update today. In the figure below, there's no mention of a restart required. I also followed the two links, but found no mention there either. I'm pretty sure that the info shown here was the same prior to the update.
When you look at the Updates list in the Mac App Store, it will indicate in the info if a restart is required. Below is an example of this:



You will see the words Restart Required followed by an icon of a white triangle within a grey circle (looks like a reverse play button).

Prior to installing the update, just check the info against each update to see whether any of them require a restart.

Security updates and OS updates usually require a restart. Most other apps don't.