#!/bin/sh
set -e

kill_child_jobs() {
    echo "In kill_child_jobs()..."
    # From https://stackoverflow.com/a/23336595
    # Kills all child processes, not just jobs.
    pkill -P $$
}
cleanup() {
    kill_child_jobs
}

# From https://unix.stackexchange.com/a/240736
for sig in INT QUIT HUP TERM; do
  trap "
    cleanup
    trap - $sig EXIT
    kill -s $sig "'"$$"' "$sig"
done
trap cleanup EXIT

yes aa &
yes disowned & builtin disown || true
sleep 100 &

wait