linux 开机启动 程序

#!/bin/bash
### BEGIN INIT INFO
# Provides:          hello_world
# Required-Start:    $local_fs $network $syslog
# Required-Stop:     $local_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Start Hello World at boot time
# Description:       Enable service provided by Hello World.
### END INIT INFO

case "$1" in
    start)
        echo "Hello World!"
        ;;
    stop)
        echo "Stopping Hello World"
        ;;
    restart)
        $0 stop
        $0 start
        ;;
    *)
        echo "Usage: /etc/init.d/hello_world {start|stop|restart}"
        exit 1
        ;;
esac

exit 0

chmod +x /etc/init.d/hello_world
update-rc.d hello_world defaults

[Unit]
Description=Hello World Service
After=network.target

[Service]
ExecStart=/bin/echo Hello World!
Restart=always

[Install]
WantedBy=multi-user.target

systemctl enable hello_world.service
systemctl start hello_world.service