# Pastebin L1e8JZxX
    if grep -q -F "0::" < /proc/self/cgroup; then
        # Hybrid or pure v2 mode available.
        if [ "$(stat -f --print=%T /sys/fs/cgroup)" = "cgroup2fs" ]; then
            base_cg="/sys/fs/cgroup$(grep -F '0::' < /proc/self/cgroup | cut -d : -f 3)"
        else
            base_cg="/sys/fs/cgroup/unified$(grep -F '0::' < /proc/self/cgroup | cut -d : -f 3)"
        fi
    else
        # Only name=systemd available
        base_cg="/sys/fs/cgroup/systemd$(grep -F :name=systemd: < /proc/self/cgroup | cut -d : -f 3)"
    fi 
    # Sanity check, this cgroup exists.
    test -d "$base_cg"