#!/bin/bash

set -eu
set -o pipefail

if [ -f /sbin/initctl ]; then
    echo "upstart"
elif [ -f /usr/bin/systemctl ]; then
    echo "systemd"
elif [ -f /sbin/init ]; then
    if [ -f /bin/systemd ]; then
        echo "systemd"
    else
        echo "sysv"
    fi
else
    echo "Unknown init system"
    exit 1
fi
