# Shell输入输出

### 1. echo

`echo` 输出变量，并自动换行

### 2. printf

格式化输出`printf format-string [arguments...]`\
​

```shell
 
printf "%-10s %-8s %-4s\n" 姓名 性别 体重kg  
printf "%-10s %-8s %-4.2f\n" 郭靖 男 66.1234
printf "%-10s %-8s %-4.2f\n" 杨过 男 48.6543
printf "%-10s %-8s %-4.2f\n" 郭芙 女 47.9876

:<<'
姓名     性别   体重kg
郭靖     男      66.12
杨过     男      48.65
郭芙     女      47.99
'
```

### 3. read

```shell
# 从标准输入读取，赋值给name
read name 
```


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