使用 sed 在两个正则表达式之间打印行 [英] Print lines between two regex using sed

问题描述

我有一个包含多个部分的文本文件，我想打印其中一个部分.

I have a text file which contains multiple sections and I want to print one of those sections.

文件的一部分看起来像

3. line 3
4. line 4

## Screenshots ##

1. line 1
2. line 2
3. line 3
4. line 4

## Changelog ##

3. line 3
4. line 4

从这里我想检索 ## Screenshots ## 和下一部分开始之间的所有行.下一部分是 ## Changelog ##，但它可以是任何内容.所以我们唯一可以依赖的是它会以 ## 开头.

From this I want to retrieve all lines between ## Screenshots ## and the starting of the next section. Here the next section is ## Changelog ##, but it could be anything. So the only thing which we can depend on is that it will start with ##.

从另一个线程，我找到了以下代码

sed -e "H;/${pattern}/h" -e '$g;$!d' $file

我修改为

sed -e "H;/## Screenshots ##/h" -e '$g;$!d' readme.md

现在，它检索从 ## Screenshots ## 开始的所有行，但它会打印所有行，直到文件末尾.

Now, it retrieves all lines starting from ## Screenshots ##, but it prints all lines till the end of the file.

然后我把它传送到另一个 sed 就像

I then piped it to another sed like

sed -e "H;/## Screenshots ##/h" -e '$g;$!d' readme.md | sed "/^##/q" 

但现在只能打印

## Screenshots ##

无论如何我可以打印屏幕截图部分中的所有行吗?

Is there anyway I can print all lines in the screenshots section?

推荐答案

awk '/pattern/{p=1;print;next} p&&/^##/{p=0};p' file

以截图"为例:

kent$  awk '/^## Screenshot/{p=1;print;next} p&&/^##/{p=0};p' file
## Screenshots ##

1. line 1
2. line 2
3. line 3
4. line 4

编辑添加说明

awk '/^## Screenshot/{p=1;print;next} : if match pattern, set p=1,print the line,read next line,(stop processing following scripts)
p&&/^##/{p=0}                         : if p==1 and match /##/ again (next section), set p=0
;p' file                              : if p==1, print the line

仅 sed

sed -n '/## Screensh/,/##/{/Scree/{p;n};/##/{q};p}' file

EDIT2 为 sed cmd 添加说明

EDIT2 add explanation to sed cmd

-n                 -> not print
'/## Screen/, /##/ -> match range, I guess you knew it already
{                  -> if in this range
    /Scree/        -> and line matches /Screenshot/
        {p;n};     -> do print line, and read next row (skip doing rest processing)
    /##/           -> if line matches "##"
        q;         -> quit, we have done all printing
    p              -> if we come to here, print the line
}

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