Shell脚本 ---执行脚本前，权限最好chmod a+x filename

[root@localhost ~]# echo $(( 13 % 3 ))
1
#注释：这个有没有空格是关键！！

交互式脚本：变量内容由用户决定

     [root@localhost ~]# vi sh02.sh 
      1 #!/bin/bash
      2 # Program:
      3 #    User inputs his first name and last name. Program shows his full name.
      4 # History:
      5 PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:~/bin
      6 export PATH
      7 read -p "Please input your first name : " firstname
      8 read -p "Please input your last name : " lastname
      9 echo -e "\nYour full name is :$firstname $lastname "

[root@localhost ~]# sh sh02.sh 
Please input your first name : Gao
Please input your last name : Zhenan

Your full name is :Gao Zhenan 

随日期变化：利用日期进行文件的创建：

[root@localhost shelldemo]# cat sh03.sh 
#!/bin/bash
#Program:
#    creates three files ,which named by user's input
#     and date command.
# History :
# 2013/06/10
PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:~/bin
export PATH
#1、让用户输入文件名，并取得fileuser这个变量；
echo -e "I will use 'touch' command to create 3 files."
read -p "Please input your filename: " fileuser
#2、为了避免用户随意按【enter】，利用变量功能分析文件名是否有设置
filename=${fileuser:-"filename"}
# 3、开始利用date 命令来取得所需要的文件名了。
date1=$(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}
#4、创建文件名
touch "$file1"
touch "$file2"
touch "$file3"

运行结果：

[root@localhost shelldemo]# date
2013年 05月 04日 星期六 07:37:54 CST
[root@localhost shelldemo]# sh sh03.sh 
I will use 'touch' command to create 3 files.
Please input your filename: file
[root@localhost shelldemo]# ll
总计 8
-rw-r--r-- 1 root root   0 05-04 07:39 file20130502
-rw-r--r-- 1 root root   0 05-04 07:39 file20130503
-rw-r--r-- 1 root root   0 05-04 07:39 file20130504
[root@localhost shelldemo]# 

数值运算：简单的加减乘除

[root@localhost shelldemo]# vi sh04.sh

      1 #!/bin/bash
      2 # Program
      3 #    User inputs 2 integer numbers;program will cross these two numbers.
      4 PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:~/bin
      5 export  PATH
      6 echo -e "You should input 2 numbers. I will cross them! \n"
      7 read -p "first number: " firstnu
      8 read -p "second number: " secnu
      9 total=$(( $firstnu*$secnu ))
     10 echo -e "\nThe result of $firstnu x $secnu is ==> $total"

运行结果：

[root@localhost shelldemo]# sh sh04.sh 
You should input 2 numbers. I will cross them! 

first number: 23
second number: 2

The result of 23 x 2 is ==> 46
[root@localhost shelldemo]#