truncate shell命令输出从最后一行匹配一个字符串，直到EOF

Question

我想截断一个shell脚本的输出，只打印匹配字符串/正则表达式和EOF的最后一行之间的部分。

如letsencrypt certbot renew --post-hook "service apache2 reload; service nginx reload"运行时，我得到这样的

... 
http-01 challenge for domain1.tld 
Waiting for verification... 
Cleaning up challenges 

------------------------------------------------------------------------------- 
new certificate deployed without reload, fullchain is 
/etc/letsencrypt/live/domain1.tld/fullchain.pem 
------------------------------------------------------------------------------- 

------------------------------------------------------------------------------- 
Processing /etc/letsencrypt/renewal/domain2.tld 
------------------------------------------------------------------------------- 
Renewing an existing certificate 
Performing the following challenges: 
http-01 challenge for domain.tld 
http-01 challenge for www.domain2.tld 
Waiting for verification... 
Cleaning up challenges 

------------------------------------------------------------------------------- 
new certificate deployed without reload, fullchain is 
/etc/letsencrypt/live/domain2.tld/fullchain.pem 
------------------------------------------------------------------------------- 
** DRY RUN: simulating 'certbot renew' close to cert expiry 
**   (The test certificates below have not been saved.) 

Congratulations, all renewals succeeded. The following certs have been renewed: 
    /etc/letsencrypt/live/domain1.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain2.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain3.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain4.tld/fullchain.pem (success) 
** DRY RUN: simulating 'certbot renew' close to cert expiry 
**   (The test certificates above have not been saved.) 
Running post-hook command: service apache2 reload; service nginx reload 
Output from service: 
* Reloading web server apache2 
* 
* Reloading nginx configuration nginx 
    ...done. 

现在我想拥有的是最后-------行之后的一切，所以期望的结果将是

** DRY RUN: simulating 'certbot renew' close to cert expiry 
**   (The test certificates below have not been saved.) 

Congratulations, all renewals succeeded. The following certs have been renewed: 
    /etc/letsencrypt/live/domain1.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain2.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain3.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain4.tld/fullchain.pem (success) 
** DRY RUN: simulating 'certbot renew' close to cert expiry 
**   (The test certificates above have not been saved.) 
Running post-hook command: service apache2 reload; service nginx reload 
Output from service: 
* Reloading web server apache2 
* 
* Reloading nginx configuration nginx 
    ...done. 

我想过一些tail -n 15命令，但我不想每次添加新域时调整我的脚本。

感谢您的帮助！

---

编辑：在此期间，我发现我自己的一个解决方案，它是不是像你一样@ anubhava的

cnt1=`grep -n "\----" certbot.log | tail -n1 | awk -F : '{ print $1 }'` 
cnt2=`wc -l certbot.log | awk '{ print $1 }'` 
cnt3=$((cnt2-cnt1)) 
tail -n $cnt3 certbot.log 

Answer 1

您可以使用awk此：

awk '/^-{6}/{p=1; str=""; next} p{str = str $0 ORS} END{printf "%s", str}' file 

这awk命令匹配------作为任何行的开始文本，一旦发现它，我们将标志p设置为1并将缓冲区str初始化为空。接下来，如果设置了标志p，我们继续将每行添加到缓冲区str中。

请注意，如果我们遇到另一个------，那么我们将str重新初始化为空，因此仅保留来自最后匹配事件的行。

输出：

** DRY RUN: simulating 'certbot renew' close to cert expiry 
**   (The test certificates below have not been saved.) 

Congratulations, all renewals succeeded. The following certs have been renewed: 
    /etc/letsencrypt/live/domain1.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain2.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain3.tld/fullchain.pem (success) 
    /etc/letsencrypt/live/domain4.tld/fullchain.pem (success) 
** DRY RUN: simulating 'certbot renew' close to cert expiry 
**   (The test certificates above have not been saved.) 
Running post-hook command: service apache2 reload; service nginx reload 
Output from service: 
* Reloading web server apache2 
* 
* Reloading nginx configuration nginx 
    ...done. 

---

替代解决方案是之前和awk并打印第一场比赛后使用tac：

tac file | awk '/^-{6}/{exit} 1' | tac