How to only read the last line from a text file

Question

I am working on a tool project. I need to grab the last line from a file & assign into a variable. This is what I have tried:

line=$(head -n $NF input_file)
echo $line

Maybe I could read the file in reverse then use

line=$(head -n $1 input_file)
echo $line

Any ideas are welcome.

Point to be noted here is `$NF` is `awk`'s terminology so not sure why you have mentioned in shell command. — RavinderSingh13, Dec 29 '18 at 04:09

score 2 · Accepted Answer · edited Dec 29 '18 at 06:23

2

Use tail ;)

line=$(tail -n 1 input_file)
echo $line

edited Dec 29 '18 at 06:23

Benjamin W.

answered Dec 29 '18 at 04:02

Gnik

score 2 · Answer 2 · answered Dec 29 '18 at 04:06

2

Combination of tac and awk here. Benefit in this approach could be we need NOT to read complete Input_file in it.

tac Input_file | awk '{print;exit}'

answered Dec 29 '18 at 04:06

RavinderSingh13

score 1 · Answer 3 · answered Dec 29 '18 at 04:12

1

With sed or awk :

sed -n '$p' file
sed '$!d' file
awk 'END{print}' file

However, tail is still the right tool to do the job.

answered Dec 29 '18 at 04:12

Til

3 Answers3