您可以尝试使用awk:

awk '/blah/{getline; print}' logfile

you can use grep, then take lines in jumps: grep -A1 'blah' logfile | awk 'NR%3==2' you can also take n lines after match, for example: seq 100 | grep -A3 .2 | awk 'NR%5==4' 15 25 35 45 55 65 75 85 95 explanation - here we want to grep all lines that are *2 and take 3 lines after it, which is *5. seq 100 | grep -A3 .2 will give you: 12 13 14 15 -- 22 23 24 25 -- ... the number in the modulo (NR%5) is the added rows by grep (here it's 3 by the flag -A3), +2 extra lines because you have current matching line and also the -- line that the grep is adding.

使用grep可以输出行号(-n)。通过<num>:和<num>-，匹配和下一行之间的输出是不同的:

# grep -A1 -n '230 Login successful."$' /var/log/vsftpd.log
1:Sat Nov  5 03:29:43 2022 [pid 10] [foo] FTP response: Client "10.1.1.1", "230 Login successful."
2-Sat Nov  5 03:29:43 2022 [pid 10] [foo] FTP response: Client "10.1.1.1", "221 Goodbye."
3:Sat Nov  5 04:44:41 2022 [pid 10] [foo] FTP response: Client "10.1.1.1", "230 Login successful."
4-Sat Nov  5 04:44:42 2022 [pid 10] [foo] FTP response: Client "10.1.1.1", "221 Goodbye."

这样我们就可以过滤输出，只得到每个匹配的下一行:

# grep -A1 -n '230 Login successful."$' /var/log/vsftpd.log | grep -E "^[0-9]+-" | cut -d"-" -f2-
Sat Nov  5 03:29:43 2022 [pid 10] [foo] FTP response: Client "10.1.1.1", "221 Goodbye."
Sat Nov  5 04:44:42 2022 [pid 10] [foo] FTP response: Client "10.1.1.1", "221 Goodbye."

reaim的回答很好，对我很有用。将其扩展到打印模式之后的第7行是很简单的

awk -v lines=7 '/blah/ {for(i=lines;i;--i)getline; print $0 }' logfile

如果你想坚持使用grep:

grep -A1 'blah' logfile | grep -v "blah"

或者使用sed:

sed -n '/blah/{n;p;}' logfile

我不知道有什么方法可以用grep来做到这一点，但是使用awk可以达到相同的结果:

awk '/blah/ {getline;print}' < logfile