SHELL-----全局變量與局部變量

變量的作用域:

一、全局變量：

任何地方都生效的變量，默認情況下，腳本主體內定義全局變量，函數內可以用，函數外也可以用

 

[root@server ~]# vim overall.sh 
#!/bin/bash

function fun1() {
    temp=$[ $value + 5 ]
    result=$[ $temp * 2 ]
}

temp=4
value=6

fun1

echo "The result is $result"
if [ $temp -gt $value ];then
    echo "temp is larger"
else
    echo "temp is smaller"
fi
[root@server ~]# sh overall.sh 
The result is 22
temp is larger

 

二、局部變量：

定義方法： local value

[root@server ~]# vim local.sh 
#!/bin/bash

function fun1() {
    local temp=$[ $value + 5 ]
    result=$[ $temp * 2 ]
}

temp=4
value=6

fun1

echo "The result is $result"
if [ $temp -gt $value ];then
    echo "temp is larger"
else
    echo "temp is smaller"
fi
[root@server ~]# sh local.sh 
The result is 22
temp is smaller