假设我有以下类型的文件:
<?xml version="1.0" encoding="utf-8"?>
<preferences>
<section id="widgets">
<value id="version" xml:space="preserve">1</value>
</section>
<section id="wuid-b2a8e6b8-6619-714e-9cfe-466c27c90902">
<value id="path to widget data" xml:space="preserve">{Preferences}widgets/opera-adblock-1.3.4-1.oex</value>
</section>
<section id="wuid-0c5cfdb2-8e51-f149-a1e7-51d66240ed7a">
<value id="path to widget data" xml:space="preserve">{Preferences}widgets/flag-button-1.5.4-1.oex</value>
</section>
</preferences>
我的任务是在最后一次出现
</section>
后立即添加文本。看看这两个似乎使用
tac
会更简单,但我也不明白如何做到这一点: Using sed to append a string to the fourth occurrence of a pattern , http://www.unix.com/unix-dummies-questions-answers/46294-add-line-after-last-occurnace-pattern.html#post302149709谢谢。
最佳答案
在字符串第一次出现之前添加内容更容易:
sed '/<\/preferences>/i\ADD SOME TEXT\nADD SOME MORE TEXT' file
结果:
<?xml version="1.0" encoding="utf-8"?>
<preferences>
<section id="widgets">
<value id="version" xml:space="preserve">1</value>
</section>
<section id="wuid-b2a8e6b8-6619-714e-9cfe-466c27c90902">
<value id="path to widget data" xml:space="preserve">{Preferences}widgets/opera-adblock-1.3.4-1.oex</value>
</section>
<section id="wuid-0c5cfdb2-8e51-f149-a1e7-51d66240ed7a">
<value id="path to widget data" xml:space="preserve">{Preferences}widgets/flag-button-1.5.4-1.oex</value>
</section>
ADD SOME TEXT
ADD SOME MORE TEXT
</preferences>
您可以阅读有关如何在字符串 here 之前插入一行的更多信息。哈。
关于Sed:在最后一次出现后追加,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/14804158/