29 lines
479 B
Markdown
29 lines
479 B
Markdown
---
|
|
title: 2.3、shell(4)-使用技巧
|
|
date: 2018-3-6 00:52:25
|
|
tags:
|
|
- linux
|
|
- shell
|
|
categories:
|
|
- linux
|
|
---
|
|
|
|
#### 判断上一条命令执行是否成功
|
|
`$?`变量的值是上一条命令执行的返回值
|
|
通过判断这个变量的值 , 可以知道上一条命令是否执行成功
|
|
```bash
|
|
if [ $? -eq 0 ];then
|
|
echo "执行成功"
|
|
else
|
|
echo "执行失败"
|
|
fi
|
|
```
|
|
<!-- more -->
|
|
|
|
#### 逐行读取文件
|
|
```bash
|
|
while read LINE
|
|
do
|
|
echo $LINE
|
|
done < test.txt
|
|
``` |