truncate shell命令輸出從最後一行匹配一個字符串，直到EOF

Question

我想截斷一個shell腳本的輸出，只打印匹配字符串/正則表達式和EOF的最後一行之間的部分。

如letsencrypt certbot renew --post-hook "service apache2 reload; service nginx reload"運行時，我得到這樣的

... 
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. 

現在我想擁有的是最後-------行之後的一切，所以期望的結果將是

** 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. 

我想過一些tail -n 15命令，但我不想每次添加新域時調整我的腳本。

感謝您的幫助！

---

編輯：在此期間，我發現我自己的一個解決方案，它是不是像你一樣@ 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 

這awk命令匹配------作爲任何行的開始文本，一旦發現它，我們將標誌p設置爲1並將緩衝區str初始化爲空。接下來，如果設置了標誌p，我們繼續將每行添加到緩衝區str中。

請注意，如果我們遇到另一個------，那麼我們將str重新初始化爲空，因此僅保留來自最後匹配事件的行。

輸出：

** 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. 

---

替代解決方案是之前和awk並打印第一場比賽後使用tac：

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