grep search + next line

Question

With the grep command, I found the text I need as follows:

grep 'C02' ~/temp/log.txt

Now, wherever I find the desired string, I would like to print the line following the found string.

For example, let's say that the desired text is abc, and abc is found on line 12, I would like to print line 13 too.

grep -A1 'abc' ~/temp/log.txt for 1 line of context After the match - see the Context Line Control subsection of the manual (man grep) — steeldriver, Nov 03 '16 at 00:44
hi and welcome to Stack Exchange! on SE, it's expected that you do some basic research before coming here for help. for example, a search for "grep show next line" returned an indirect answer in the first result and a direct answer in the second. what have you done to try to solve this problem already? — strugee, Nov 03 '16 at 02:09
You should use grep -F 'C02' instead as it is faster. grep -F matches fixed strings. such as 'C02' — Cadoiz, Nov 02 '21 at 16:52

score 62 · Answer 1 · edited Dec 10 '18 at 11:10

62

If you are using Linux system, you can try:

grep -A1 "C02" ~/temp/log.txt


OPTIONS
       -A NUM, --after-context=NUM
              Print NUM lines of trailing context after matching lines.  Places a line containing -- between contiguous groups of matches.
       -B NUM, --before-context=NUM
              Print NUM lines of leading context before matching lines.  Places a line containing -- between contiguous groups of matches.
       -C NUM, --context=NUM
              Print NUM lines of output context.  Places a line containing -- between contiguous groups of matches.

You can use awk also as:

awk '/C02/{print;getline;print}' ~/temp/log.txt

edited Dec 10 '18 at 11:10

Community

1

answered Nov 03 '16 at 01:01

Kamaraj

4,365

3

also, sed -n '/C02/{N; p}' ~/temp/log.txt – Sundeep Nov 03 '16 at 01:53
1

For anyone wondering, for example -A9 will add 9 rows so that there are 10 shown in the output, not just the 0th and the ninth row. – questionto42 Sep 08 '22 at 18:10

grep search + next line

1 Answers1