linux bash学习(一)

1.请你以 read 指令的用途，撰写一个 script ，他可以让使用者输入：1. first name 与 2. last name， 最后并且在屏幕上显示：“Your full name is: ”的内容：

#!/bin/bash
#Program:
#       use input his first name and last name.Program shows his full name.
#History:
#2017/07/27     lzyer   release
read -p "Please input your first name:" firstname
read -p "Please input your last name:" lastname
echo "Your full name is : ${firstname}.${lastname}"

2.随日期变化：利用 date 进行文件的创建

#!/bin/bash
#Program:
#       Program creates three files, which named by user‘s input and date command.
#History
#2017/07/28     lzyer  First release

echo "I will use ‘touch‘ command to create 3 file."
read -p "Please input your filename :" fileuser
filename=${fileuser:-"filename"}
date1=$(date --date=‘2 days ago‘ +%Y%m%d)
date2=$(date --date=‘1 days ago‘ +%Y%m%d)
date3=$(date +%Y%m%d)
file1=${filename}${date1}
file2=${filename}${date2}
file3=${filename}${date3}

touch "${file1}" "${file2}" "${file3}"

3.数值运算：简单的加减乘除

#!/bin/bash
#Program:
#       use input 2 integer numbers; program will cross these two numbers.
#History:
#2017/07/28     lzyer First release
echo "you should input 2 numbers, i will multipfying them !"
read -p "first numbe: " firstnumber
read -p "second number: " secondnumber
total=$((${firstnumber}*${secondnumber}))
echo "The result of ${firstnumber} x ${secondnumber} ==> ${total}"

4.sh和source的差异性