How do I get the last non-empty line of a file using tail in Bash?

Question

How do I get the last non-empty line using tail under Bash shell?

For example, my_file.txt looks like this:

hello
hola
bonjour
(empty line)
(empty line)

Obviously, if I do tail -n 1 my_file.txt I will get an empty line. In my case I want to get bonjour. How do I do that?

Answer 1

How about using grep to filter out the blank lines first?

$ cat rjh
1
2
3


$ cat rjh | grep "." | tail -1
3

Answer 2

Use tac, so you dont have to read the whole file:

tac FILE |egrep -m 1 .

Answer 3

You can use Awk:

awk '/./{line=$0} END{print line}' my_file.txt

This solution has the advantage of using just one tool.

Answer 4

if you want to omit any whitespaces, ie, spaces/tabs at the end of the line, not just empty lines

awk 'NF{p=$0}END{print p}' file