29 lines
470 B
Markdown
29 lines
470 B
Markdown
---
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title: shell(4)-使用技巧
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date: 2018-5-6 00:52:25
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tags:
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- linux
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- shell
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categories:
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- linux
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---
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#### 判断上一条命令执行是否成功
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`$?`变量的值是上一条命令执行的返回值
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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
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```bash
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if [ $? -eq 0 ];then
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echo "执行成功"
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else
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echo "执行失败"
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fi
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```
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<!-- more -->
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#### 逐行读取文件
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```bash
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while read LINE
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do
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echo $LINE
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done < test.txt
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``` |