为什么我的 init.d 脚本在手动调用时有效，但在启动时无效？

我的目标

在启动时使用参数运行 x.flux

我的尝试

一个 init.d 脚本。它可以通过手动调用

sudo /etc/init.d/xflux start
[ ok ] Starting xflux (via systemctl): xflux.service.

我的问题

程序“x.flux”在启动后没有正常运行，即屏幕没有按预期变红。在 cli 中使用相同的参数启动后手动调用它可以按预期工作。

日志和假设

我收到

sudo service xflux status
● xflux.service - LSB: xflux start script
   Loaded: loaded (/etc/init.d/xflux; generated; vendor preset: enabled)
   Active: inactive (dead) since [...] CEST; 18min ago
     Docs: man:systemd-sysv-generator(8)
  Process: 4153 ExecStop=/etc/init.d/xflux stop (code=exited, status=0/SUCCESS)
  Process: 4065 ExecStart=/etc/init.d/xflux start (code=exited, status=0/SUCCESS)

systemd[1]: Starting LSB: xflux start script...
xflux[4065]: Couldn't open display (null)
xflux[4065]: .
xflux[4065]: [10B blob data]
xflux[4065]: --------
xflux[4065]: Welcome to xflux (f.lux for X)
xflux[4065]: This will only work if you're running X on console.
systemd[1]: Started LSB: xflux start script.
systemd[1]: Stopping LSB: xflux start script...
systemd[1]: Stopped LSB: xflux start script.

所以这可能是can-not-open-display-null-error-how-can-i-fix-this但我不明白如何解决这个问题，如果它确实是问题。

剧本

为了完成这里的脚本

#! /bin/sh
### BEGIN INIT INFO
# Provides:          xflux
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: xflux start script
### END INIT INFO

# Do NOT "set -e"

# PATH should only include /usr/* if it runs after the mountnfs.sh script
PATH=/sbin:/usr/sbin:/bin:/usr/bin
DESC="Description of the service"
NAME=xflux
RUNDIR=/usr/local/bin/$NAME
DAEMON=/usr/local/bin/$NAME
DAEMON_ARGS="hereGoesMyLocationAsParam"
PIDFILE=/var/run/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME

# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0

# Read configuration variable file if it is present
[ -r /etc/default/$NAME ] && . /etc/default/$NAME

# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh

# Define LSB log_* functions.
# Depend on lsb-base (>= 3.2-14) to ensure that this file is present
# and status_of_proc is working.
. /lib/lsb/init-functions

#
# Function that starts the daemon/service
#
do_start()
{
    # Return
    #   0 if daemon has been started
    #   1 if daemon was already running
    #   2 if daemon could not be started
    start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test > /dev/null \
        || return 1
    start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON -- \
        $DAEMON_ARGS \
        || return 2
    # Add code here, if necessary, that waits for the process to be ready
    # to handle requests from services started subsequently which depend
    # on this one.  As a last resort, sleep for some time.
}

#
# Function that stops the daemon/service
#
do_stop()
{
    # Return
    #   0 if daemon has been stopped
    #   1 if daemon was already stopped
    #   2 if daemon could not be stopped
    #   other if a failure occurred
    start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE --name $NAME
    RETVAL="$?"
    [ "$RETVAL" = 2 ] && return 2
    # Wait for children to finish too if this is a daemon that forks
    # and if the daemon is only ever run from this initscript.
    # If the above conditions are not satisfied then add some other code
    # that waits for the process to drop all resources that could be
    # needed by services started subsequently.  A last resort is to
    # sleep for some time.
    start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $DAEMON
    [ "$?" = 2 ] && return 2
    # Many daemons don't delete their pidfiles when they exit.
    rm -f $PIDFILE
    return "$RETVAL"
}

#
# Function that sends a SIGHUP to the daemon/service
#
do_reload() {
    #
    # If the daemon can reload its configuration without
    # restarting (for example, when it is sent a SIGHUP),
    # then implement that here.
    #
    start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE --name $NAME
    return 0
}

case "$1" in
  start)
    [ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
    do_start
    case "$?" in
        0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
        2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
    esac
    ;;
  stop)
    [ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
    do_stop
    case "$?" in
        0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
        2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
    esac
    ;;
  status)
    status_of_proc "$DAEMON" "$NAME" && exit 0 || exit $?
    ;;
  #reload|force-reload)
    #
    # If do_reload() is not implemented then leave this commented out
    # and leave 'force-reload' as an alias for 'restart'.
    #
    #log_daemon_msg "Reloading $DESC" "$NAME"
    #do_reload
    #log_end_msg $?
    #;;
  restart|force-reload)
    #
    # If the "reload" option is implemented then remove the
    # 'force-reload' alias
    #
    log_daemon_msg "Restarting $DESC" "$NAME"
    do_stop
    case "$?" in
      0|1)
        do_start
        case "$?" in
            0) log_end_msg 0 ;;
            1) log_end_msg 1 ;; # Old process is still running
            *) log_end_msg 1 ;; # Failed to start
        esac
        ;;
      *)
        # Failed to stop
        log_end_msg 1
        ;;
    esac
    ;;
  *)
    #echo "Usage: $SCRIPTNAME {start|stop|restart|reload|force-reload}" >&2
    echo "Usage: $SCRIPTNAME {start|stop|status|restart|force-reload}" >&2
    exit 3
    ;;
esac

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