从 systemd 脚本运行时“systemctl hibernate”返回 1

Question

因此，我有一个小的 systemd 脚本，该脚本应该在我的笔记本电脑处于挂起模式 x 秒后使其进入休眠状态（文件名为/lib/systemd/system-sleep/0000rtchibernate.sh）：

#!/bin/bash
# Script name: /usr/lib/systemd/system-sleep/0000rtchibernate.sh
# Purpose: Auto hibernates after a period of sleep
# Edit the "autohibernate" variable below to set the number of seconds to sleep.
curtime=$(date +%s)
autohibernate=10  #for testing purposes
sleeptime=2
logging=true
logfile="/lib/systemd/system-sleep/0000rtchibernate.log"
skipfile="/lib/systemd/system-sleep/0000rtchibernate.skip"
lockfile="/tmp/rtchibernate.lock"
echo "$curtime $1" >>/tmp/autohibernate.log

if [ "$2" = "hibernate" ]; then
        if [ "$logging" = true ]; then
            echo "$(date) : Hibernating, doing nothing" >> $logfile
        fi

    exit 0
fi

if [ "$1" = "pre" ]; then
    # only set timer if file 0000rtchibernate.skip doesn't exist
    if [ ! -f $skipfile ]; then
        # Suspending.  Record current time, and set a wake up timer.
        if [ "$logging" = true ]; then
            echo "$(date) : Suspending" >> $logfile
        fi
        echo "$curtime" > $lockfile
        rtcwake -m no -s $autohibernate
    fi
fi

if [ "$1" = "post" ]; then
    if [ -f $skipfile ]; then
        # if skipfile is present on resume, remove it
        if [ "$logging" = true ]; then
            echo "$(date) : Removing skipfile" >> $logfile
        fi
        rm $skipfile
    else
        # Coming out of sleep
        sustime=$(cat $lockfile)
        rm $lockfile

        # Did we wake up due to the rtc timer above?
        if [ $(($curtime - $sustime)) -ge $((autohibernate-5)) ]; then

            if [ "$logging" = true ]; then
                echo "$(date) : Hibernating" >> $logfile
            fi

            # Then hibernate
            /bin/systemctl hibernate
            return_val=$?
            if [ "$logging" = true ]; then
                echo "$(date) : Return value of systemctl hibernate was $return_val" >> $logfile
            fi
            # if hibernation fails, create skipfile and suspend
            if [ "$return_val" -gt 0 ]; then
                if [ "$logging" = true ]; then
                    echo "$(date) : Hibernation failed. Creating skipfile and suspending" >> $logfile
                fi
                touch $skipfile
                /bin/systemctl suspend
            fi

        else
            if [ "$logging" = true ]; then
                echo "$(date) : Waking up early, not hibernating" >> $logfile
            fi
            # Otherwise cancel the rtc timer and wake up normally.
            rtcwake -m no -s 1
        fi
    fi
fi

（代码最初来自这里，我只适配了systemd）

挂起笔记本电脑时脚本运行良好，以下是日志输出：

Di 20. Mär 10:53:31 CET 2018 : Suspending
Di 20. Mär 10:53:44 CET 2018 : Hibernating
Di 20. Mär 10:53:44 CET 2018 : Return value of systemctl hibernate was 1
Di 20. Mär 10:53:44 CET 2018 : Hibernation failed. Creating skipfile and suspending

我的问题是/bin/systemctl hibernate和/bin/systemctl suspend的返回值都是 1，并没有按照预期执行，尽管从终端窗口运行时一切都正常。顺便说一句，我在 Ubuntu 18.04 上。任何帮助都感激不尽 :-)