Comments by "Immudzen" (@Immudzen) on "Arch User Reacts To Linus Tech Tips Linux Challenge Pt 2" video.

Updating without restarting on a modern GUI Linux is remarkable hard to do. You can install the updates but since the files are reference counted the old files are still being used by programs that already have them open. In order to actually do the upgrade you have to shut down every program using the files and then reopen them again. The more towards the core a library is the harder this is to do. If a library like gtk was upgraded you would have to shut down X and restart it. At some point you are better off just rebooting and guaranteeing the update is applied. I have seen systems before get broken into because they never restarted. The software running was still vulnerable even though the vulnerable software could no longer be seen on the filesystem. The admin thought they had applied the update and everything was fine when it was not.
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