如何在 egrep 中使用变量作为搜索字符串答案

【问题标题】：How to use varible as search string in egrep如何在 egrep 中使用变量作为搜索字符串
【发布时间】：2017-04-14 11:31:07
【问题描述】：

我想使用 egrep 从文件中执行多字符串搜索，但使用变量来存储搜索字符串值。这将帮助我以编程方式更改搜索字符串。示例：-

SEARCHSTRING='typesetting industry|printer took|specimen'
cat /tmp/input.file|egrep $SEARCHSTRING > /tmp/output.file

input.file 内容：

*Lorem Ipsum is simply dummy text of the printing and typesetting industry.  
Lorem Ipsum has been the industry's standard dummy text ever since the  
1500s, when an unknown printer took a galley of type and scrambled it to  
make a type specimen book. It has survived not only five centuries,   
but also the leap into electronic*

output.file 内容（预期）：

*Lorem Ipsum is simply dummy text of the printing and typesetting industry.  
1500s, when an unknown printer took a galley of type and scrambled it to  
make a type specimen book. It has survived not only five centuries,*

请帮忙

【问题讨论】：

标签： bash shell unix scripting grep

【解决方案1】：

双引号变量，也使用grep -E而不是egrep

egrep  "$SEARCHSTRING" inputfile
Lorem Ipsum is simply dummy text of the printing and typesetting industry.
1500s, when an unknown printer took a galley of type and scrambled it to
make a type specimen book. It has survived not only five centuries,

【讨论】：