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    <title>曲径通幽论坛 - FAQ</title>
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    <description>Latest 20 threads of FAQ</description>
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      <title>如何检测命令行参数为非空？</title>
      <link>http://www.groad.net/bbs/forum.php?mod=viewthread&amp;tid=8169</link>
      <description><![CDATA[Q： 如何检测命令行参数为非空？
A： 如果一个脚本需要检测命令行参数，那么首先需要检测命令行参数是否为非空。常用的测试选项为 -n ，如下脚本示例：
[mw_shl_code=bash,true]#!/bin/sh

if [ -n \&quot;$1\&quot; ]
then
echo -n \&quot;option is not null, you input is \\\&quot;\&quot;
e ...]]></description>
      <category>FAQ</category>
      <author>beyes</author>
      <pubDate>Sat, 30 Nov 2013 06:50:39 +0000</pubDate>
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