#! /bin/bash

test() {

        echo "未加引号,二者相同"

        echo $*

        echo $@

        # 脚本名

        echo $

        # 参数个数

        echo $#

        # 返回值

        echo $?

        echo "加入引号后对比"

        for N in "$*"

        do

           echo $N

        done

        echo "----------"

        for N in "$@"

        do

           echo $N

        done

}

test      

[root@elk01 ~]# cat calc.sh

#!/bin/bash

#

a=

b=

#加法

echo `expr $a + $b`

#减法

echo `expr $a - $b`

echo '-----乘法----'

echo `expr $a \* $b`

echo '-----除法----'

echo `expr $a / $b`

c=$[a+b]

echo $c

d=$((a*b))

echo $d