AFAIK kernel itself doesn’t send any signals to processes on shutdown/reboot, it just stops executing them. This is a job service manager (e.g. systemd) that terminates processes using SIGTERM before asking kernel to shutdown.

That’s why you launch them through systemd.

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I’m not American but my understanding is that many of those “suburban” residential blocks have sidewalks and you can walk around withing the confinement of your block. However blocks are isolated from each other and you need a car to go somewhere else.