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增加$_跟>的神奇用法 #118

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6 changes: 6 additions & 0 deletions translations/zh-CN/README.md
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Expand Up @@ -212,13 +212,16 @@ bash中有 _非常多_ 的环境变量。你会非常频繁地遇到它们，这
| `$1 … $9` | 第1个到第9个参数列表 |
| `${10} … ${N}` | 第10个到N个参数列表 |
| `$*` or `$@` | 除了`$0`外的所有位置参数 |
| `$_` | 上一条指令的最后一个参数 |
| `$#` | 不包括`$0`在内的位置参数的个数 |
| `$FUNCNAME` | 函数名称（仅在函数内部有值） |

在下面的例子中，位置参数为：`$0='./script.sh'`，`$1='foo'`，`$2='bar'`：

./script.sh foo bar

在执行这个指令之后，`$_`的值会变成bar（`$_`多用于类似`mkdir build && cd $_`这样的场合）

变量可以有 _默认_ 值。我们可以用如下语法来指定默认值：

```bash
Expand Down Expand Up @@ -458,6 +461,9 @@ grep da * 2> errors.txt

# 从errors.txt中读取输入
less < errors.txt

# 立即删除文件并释放文件占用的空间（如果某文件正在被程序使用（比如接连不断地写log），rm不会立刻删除这个文件（于是这个log会不断地膨胀直到把你的可用空间吃干净））
> log_to_delete.log
```

## 管道
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