实验6 shell程序设计一（1）

设计如下一个菜单驱动程序

Use one of the following options:

P:To display current directory

S:To display the name of running file

D:To display today's date and present time (要求显示为：2017-04-26 05:45:12) 

L:To see the list of files in your present working directory

W:To see who is logged in

Q:To quit this program

Enter your option and hit:

菜单程序将根据用户输入的选择项给出相应信息。要求对用户的输入忽略大小写，对于无效选项的输入给出相应提示。要求使用case语句实现以上功能，输入相应的字母后应该执行相应的命令完成每项功能，如输入P或p，就执行pwd命令。

 

#!/bin/bash

function welcome()
{
    echo -e "\n"
    echo "Use one of the following options:"
    echo "P: To display current derectory "
    echo "S: To display the name of running file"
    echo "D: To display today's date and present time"
    echo "L: To see the listing of files in your present working directory"
    echo "W: To see who is logged in"
    echo "Q: To quit this program"
    echo -n    "Enter your option and hit:"
    read a
    echo -e "\n"
}
welcome
until [ $a = q -o $a = Q ];
do
    case "$a" in
    p|P)
    pwd
    welcome
    ;;
    s|S)
    echo "The running file is $0"
    welcome
    ;;
    d|D)
    date
    welcome
    ;;
    l|L)
    ls -a
    welcome
    ;;
    w|W)
    who
    welcome
    ;;
    *)
    echo -n "Sorry,your option is wrong,please enter your option again"
    echo -e "\n"
    read a
    esac
done
echo "Thank you for your playing"
exit 0