保护ls着色后grep'ing [英] Preserve ls colouring after grep'ing

问题描述

如果我这样做

  $ ls -l --color = always 
  
 
 
 
我得到一个目录中的文件列表，有不同的文件类型等等。
 
 
 
现在，我想能够管道 ls 的彩色输出通过 grep 过滤掉一些文件我不需要。关键是我仍然希望在grep过滤器之后保留着色。
  $ ls -l --color = always | grep -E some_regex 
  
 ^在grep后失去着色
 
 
 
编辑：我使用无头服务器Ubuntu 8.10，Bash 3.2.39，几乎没有花哨的配置的安装
解决方案
您的grep可能会删除 ls 的颜色代码，因为它已打开自己的颜色。
 
 
 
您可以这样做：
  ls -l --color = always | grep --color = never pattern 
  
但是，  grep 在这里ping。不仅 grep  ping  ls 不必要（使用 glob  ），这个特殊情况是 grep 不仅通过文件名和文件统计，还通过 ls ！
 
 
 
你的问题的真正答案是：不要 grep 。从来不需要管道 ls 任何东西或捕获它的输出。  ls 仅供人类解释（例如仅在交互式外壳中查看 它是非常方便，当然）。如前所述，您可以使用globs筛选 ls 枚举的文件：
  ls -l * .txt＃显示所有文件名以.txt结尾的文件。 
 ls -l！（foo）.txt＃显示所有文件名以.txt结尾但不是foo.txt的文件。 （这需要`shopt -s extglob`开启，你可以把它放在〜/ .bashrc中）
  
 I 高度建议您阅读这两个关于此问题的优秀文档：
 
 
 
 
 
解析错误的解释 ls ：  http://mywiki.wooledge.org/ParsingLs   
 
 
  glob  s：  http://mywiki.wooledge.org/glob   
 
 
 
If I do 
$ ls -l --color=always
I get a list of files inside the directory with some nice colouring for different file types etc..

Now, I want to be able to pipe the coloured output of ls through grep to filter out some files I don't need. The key is that I still want to preserve the colouring after the grep filter.
$ ls -l --color=always | grep -E some_regex
^ I lose the colouring after grep

EDIT: I'm using headless-server Ubuntu 8.10, Bash 3.2.39, pretty much a stock install with no fancy configs
解决方案
Your grep is probably removing ls's color codes because it has its own coloring turned on.

You "could" do this:
ls -l --color=always | grep --color=never pattern
However, it is very important that you understand what exactly you're grepping here.  Not only is grepping ls unnecessary (use a glob instead), this particular case is grepping through not only filenames and file stats, but also through the color codes added by ls!

The real answer to your question is: Don't grep it.  There is never a need to pipe ls into anything or capture its output.  ls is only intended for human interpretation (eg. to look at in an interactive shell only, and for this purpose it is extremely handy, of course).  As mentioned before, you can filter what files ls enumerates by using globs:
ls -l *.txt      # Show all files with filenames ending with `.txt'.
ls -l !(foo).txt # Show all files with filenames that end on `.txt' but aren't `foo.txt'. (This requires `shopt -s extglob` to be on, you can put it in ~/.bashrc)
I highly recommend you read these two excellent documents on the matter:


Explanation of the badness of parsing ls: http://mywiki.wooledge.org/ParsingLs
The power of globs: http://mywiki.wooledge.org/glob


                        
这篇关于保护ls着色后grep'ing的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！