How to read backward from the end of file in less or more?

Question

I've found one way so far: less +G filename, but it scrolls up line-by-line only with ↑.

What's a more powerful less usage which provides scrolling by page, backward pattern search, and so on?

score 271 · Accepted Answer · answered Jun 16 '10 at 10:56

271

I'm sure someone else has a better answer, but

With "less" after you've opened the file:

G goes to the bottom of the file

^b goes up one page

? searches backwards.

As you said, you can open the file with +G and then use ? and ^b to scroll up. There are likely clever awk things you can do to achieve the same thing in a script.

answered Jun 16 '10 at 10:56

chris

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Ctrl-b works, but b (by itself) also does. – Dennis Williamson Jun 16 '10 at 13:31
Oops! I'm so conditioned to use vi keys that I just use those in less as well. Yes -- b moves you up a page in less, but only backwards one word at a time in vi. I'm impatient; I want a page at a time, and my walnut sized brain can't remember if I'm in vi or less sometimes... – chris Jun 16 '10 at 14:06
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less your file, then type 'h' => you get a nice per-operation manual. Very neat, no need for external guides or the manpage IMO. – Kharski Jan 21 '15 at 14:32
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in fact, `? = shift + /`, `/` is to search forwards. – HongboZhu May 23 '16 at 13:11
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In fact `Shift + G` goes to the bottom of the file – Alex78191 Jun 06 '18 at 21:57
@HongboZhu in us keyboard layout, but I don't think on others – eis Aug 02 '18 at 05:31
Using `+G` on the command line works for the first file. But when viewing multiple files with `less +G` only the first file will be shown from the end, the rest of the files are still shown from the beginning. – kasperd Oct 13 '18 at 09:39

score 98 · Answer 2 · answered Jun 16 '10 at 13:32

98

For variety, if you actually want/need to read a file backwards (last line first):

tac filename | less

answered Jun 16 '10 at 13:32

Dennis Williamson

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That's mostly a linux / gnuism... – chris Jun 16 '10 at 13:58
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Fun fact: `tac` is `cat` backwards – dKen Mar 21 '16 at 15:57
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This was my childhood cat's name. I don't think I realized why until now. – vaughan Nov 26 '17 at 12:46
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Anybody heard of anything like `ztac` for gzipped files (ie `zcat` but backwards)? – irbanana Dec 04 '18 at 23:16
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@irbanana: [One way](https://unix.stackexchange.com/a/132642/382). But it doesn't save any time on large files because the whole file has to be decompressed. – Dennis Williamson Dec 04 '18 at 23:47

Ruben Estrada · Answer 3 · 2019-11-30T18:48:21.043

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use:

less +F /path/to/your/file

that's less but starting from the bottom. Also, with +F, if the file is being written to while you are using less, that additional content gets output. This can be useful for logs.

Use the up arrow key to go backwards line by line or ctl+b to go page by page.

edited Nov 30 '19 at 18:48

answered Aug 01 '18 at 18:25

Ruben Estrada

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This not only goes to the end of the file, it waits for additional output at the end, like `tail -f`. If this isn't what you want, you should use `+G` instead. – Michael Hampton Aug 01 '18 at 18:31
you're right @MichaelHampton – Ruben Estrada Aug 01 '18 at 18:49
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and you can stop waiting for additional output by pressing CTRL+C. It stops waiting for new data but does not exit less. – xdevs23 Nov 07 '19 at 22:01

score 8 · Answer 4 · answered Jun 16 '10 at 10:54

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w goes up by page. ? does reverse search. h brings up online help.

answered Jun 16 '10 at 10:54

Ignacio Vazquez-Abrams

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score 4 · Answer 5 · answered Dec 10 '15 at 22:21

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tail -r | less

I don't know why anyone didn't think of this one. Tail grabs the end of a file really easy. Is -r not a common option?

answered Dec 10 '15 at 22:21

Crissa Kentavr

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Using tail (GNU coreutils) 8.13 on Ubuntu 12.02 here. No such option as `-r`. – JHH Mar 30 '16 at 06:47
I think `tail -r` is a BSD/macOS thing - those environments don't have `tac`. – fzzfzzfzz Apr 27 '17 at 15:24

score 3 · Answer 6 · answered Oct 05 '18 at 12:50

I'm surprised nobody brought this up before, but:

?pattern searches for pattern backwards.

N finds the previous match of the pattern (that is, searching backwards).

For reference, /pattern searches for pattern forward and n finds the next match of the pattern. That's the way the search is commonly used.

Shubham Singh · Answer 7 · 2019-07-10T20:35:54.110

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While using more or journalctl -xe using space bar takes you 1 page down. That worked for me. Hope this helps.

edited Jul 10 '19 at 20:35

answered Sep 12 '17 at 08:16

Shubham Singh

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score 1 · Answer 8 · answered Sep 27 '16 at 09:40

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Another alternative, after you have started less on a file:

alt + "end-key"

With "end-key" I mean the key that is usually located below the "home-key" on a keyboard.

answered Sep 27 '16 at 09:40

ria

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Gabriel Staples · Answer 9 · 2022-07-16T23:06:06.113

Open the file straight to the end (+G) with less +G path/to/filename.

It will automatically start "calculating line numbers." If the file is huge (ex: many GiB), press Ctrl + C to stop that, since it could take forever.

Now, here are some keys to navigate:

Up Arrow = scroll one line up
Down Arrow = scroll one line down
u = scroll a half page up
d = scroll a half page down
PageUp = scroll a full page up
PageDown = scroll a full page down
Use / to search forwards, pressing n to go to the next match down, and Shift + n to go to the next match up.
Use ? to search backwards, pressing n to go to the next match up, and Shift + n to go to the next match down.

References

The question itself, which reminded me of less +G filename to open the file straight to the end.
This answer.
My own knowledge.
man less

score -1 · Answer 10 · answered Jun 21 '15 at 23:11

-1

If you're looking for something specific, this might do it:

cat yourfile.txt | grep "something specific" | less

I use it for searching log files. It's still in the 'wrong' order though, but much shorter.

After reading Dennis Williamson's answer, that's my new method =)

answered Jun 21 '15 at 23:11

Rudie

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I don't need `cat` with `grep` -- `grep $StRING $FILENAME | less` – Lee Goddard Nov 10 '16 at 08:55
Imho, that's an absolutely different question. – Yaroslav Nikitenko Mar 23 '17 at 07:57

score -1 · Answer 11 · answered Oct 13 '18 at 07:23

Perhaps some people did not understood what dr01 meant. I try to put it in other words.

Open the file in less
Forward search: Enter the key /
Backward search: Enter the key ?
For both of the preceding: Enter your search term now
Press enter
Press n to search for the next finding
Press N to search for the previous finding

How to read backward from the end of file in less or more?

11 Answers11

References