#!/bin/bash

 while true

 do

     echo

     clear

     echo

     echo "        系统维护菜单        "

     echo "============================ "

     echo "      1)显示系统日期         "

     echo "      2)修改系统日期         "

     echo "      3)显示已登录用户       "

     echo "      4)重启电脑             "

     echo "      5)关机                 "

     echo "      6)退出                 "

     echo "============================ "

     echo "                            "

     echo -n "请选择："

     read sel

     case ${sel} in

         ) date +"%Y-%m-%d %H:%M";;

         ) echo -n "请输入新的日期(MMDDhhmm[[CC]YY])："

            read da

            date ${da};;

         ) who -u | awk '{print $1}';;

         ) shutdown -r now;;

         ) shutdown -h now;;

         ) break;;

     esac

     read

 done