02-2017-11-08-练习-日期开机关机¶
练习1-date¶
1 、显示当前时间,格式:2016-06-18 10:20:30
[root@centos6 ~]# date "+%Y-%m-%d %H:%M:%S"
2017-11-10 09:20:34
2 、显示前天是星期几
[root@centos6 ~]# date
Fri Nov 10 09:27:41 CST 2017
[root@centos6 ~]# date -d "@"$(echo $(date +%s) - 60*60*24*2 |bc) +%w
3
[root@centos6 ~]# date -d "-2 day" +%w
3
3 、设置当前日期为2019-08-07 06:05:10
[root@centos6 ~]# date 080706052019.10
Wed Aug 7 06:05:10 CST 2019
[root@centos6 ~]# date
Wed Aug 7 06:05:12 CST 2019
[root@centos6 ~]# date "+%Y-%m-%d %H:%M:%S"
2019-08-07 06:05:42
练习2-mingetty,shutdown¶
1、在本机字符终端登录时,除显示原有信息外,再显示当前登录终端号,主机名和当前时间 我们使用man mingetty可以获取到如下的帮助信息。
-d | insert current day (localtime), 插入当前日期 |
-l | insert line on which mingetty is running,终端类型 |
-m | inserts machine architecture (uname -m),机器架构 |
-n | inserts machine’s network node hostname (uname -n),主机名 |
-o | inserts domain name,域名 |
-r | inserts operating system release (uname -r),版本号 |
-t | insert current time (localtime),时间 |
-s | inserts operating system name,操作系统名字 |
-u | resp. U the current number of users which are currently loggedin. 显示登陆用户数量 |
-v | inserts operating system version (uname -v).操作系统版本 |
修改文件如下即可
[root@centos6 ~]# cat /etc/issue
CentOS release 6.9 (Final)
Kernel \r on an \m
current time: \d \t
hostname : \n
tty: \l
2、今天18:30自动关机,并提示用户
[root@centos6 ~]# shutdown 18:30 "computer will close"
Broadcast message from root@centos6.magedu.com
(/dev/pts/1) at 6:28 ...
The system is going down for maintenance in 722 minutes!
computer will close