How to use Undo functionality in Nano?

Question

I use the commmand line text editor nano. How do I undo an action while editing text?

For example: I typed some text and then changed my mind. Now I want to return to previous state. How?

You may want to consider changing the accepted answer here, as there is a newer, more accurate one. — Scimonster, Jul 06 '17 at 09:09

Bob Stein · Accepted Answer · 2019-10-05T23:40:33.623

243

Starting with nano version 2.3.5 in July 2014, undo/redo became standard:

Alt-U or Option-U or EscU - undo
Alt-E or Option-E or EscE - redo

It's in the help:

And if you stretch the screen wider than about 1400 pixels, there's a hint at bottom right:

If these keys don't work, check nano --version.

nano versions 2.1.10 - 2.3.4 should use the command line option -u (thanks @sil). Tip: add alias nano="nano -u" to your .bashrc (thanks @Benia). The implementation of undo during this period appears to have been buggy or incomplete.
nano versions 2.1.3 - 2.1.9 had some kind of undo feature. The -u option was not necessary.

M stands for meta.

edited Oct 05 '19 at 23:40

answered Sep 09 '15 at 12:08

Bob Stein

2,606

4

Clicking alt+u doesn't work for me to undo. – Oct 05 '16 at 08:07
7

@Benia try using Esc key instead of Alt. Let me know if that helps – Sergiy Kolodyazhnyy Oct 05 '16 at 08:13
Hi! Sadly it doesn't :, Nano prints "Unkown command" also for ESC-U. – Oct 05 '16 at 08:17
If you have an alternative or any idea what to check please publish in an answer and I will gladly give the bounty. – Oct 05 '16 at 08:56
@Benia Version check ... nano --version – Bob Stein Oct 05 '16 at 13:21
Indeed Nano is 2.2.6 and hence the prob. When I do sudo apt-get update and then sudo apt-get upgrade, it isn't change to Nano 3.x.x so I need to find a way to either update Nano individually or to upgrade the whole sys from Ubuntu 14.04 to 16.0... – Oct 05 '16 at 13:24
@Benia have you tried Sil's tip of running with the -u option? I seem to recall difficulties updating nano as well. Having a vague sense some security gnome somewhere has decided we don't need to. – Bob Stein Oct 05 '16 at 13:31
Yes: Ben@DESKTOP-NJKJAQR:/mnt/c/Users/Ben$ Nano -u No command 'Nano' found, did you mean: Command 'nano' from package 'nano' (main) – Oct 05 '16 at 13:35
Right @Benia no capital N. nano -u somefile.txt – Bob Stein Oct 05 '16 at 13:36
Oh sorry. Anyway, Nano works that way regularly 2.2.6 – Oct 05 '16 at 13:39
It doesn't change* – Oct 05 '16 at 13:40
1

Let us continue this discussion in chat. – Bob Stein Oct 05 '16 at 13:41
Mac Users: Terminal > Preferences > Settings > Keyboard > ‘Use option as meta key’ @JohnDoea – JBallin Feb 07 '18 at 05:17
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I came here to know what does that M stand for – Amr Saber Oct 26 '18 at 21:30
Alt + u works fine for me on ubuntu 16 – peter Feb 22 '19 at 11:43
I've noticed you need to do a capital U in some shells. This worked for me in GCP console. So, Alt Shift u. – G_Style Mar 07 '19 at 22:12
1

Esc + u worked for me in RHEL 8 – Zolbayar Oct 05 '19 at 07:47
Thanks @Zolbayar, I found Esc-U seems to work everywhere Alt-U does. So I added it to the answer. – Bob Stein Oct 05 '19 at 23:17
5

But I wonder why it's shown as M-U or M-E on nano. What's that M? – Zolbayar Oct 05 '19 at 23:26
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@Zolbayar also added to answer: M stands for meta. – Bob Stein Oct 05 '19 at 23:44
Esc + U works fine on Mac OS 14 (Sonoma). – Rafs Dec 18 '23 at 15:46

score 39 · Answer 2 · answered Aug 15 '13 at 14:21

39

Nano's undo code is experimental. As you'll see from the nano manual (type "man nano" in a Terminal to read that), you'll need to start nano with the -u option (so "nano -u somefile.txt"), and then you can use Alt-U to undo.

answered Aug 15 '13 at 14:21

sil

4,297

10

Thanks. There is also redo functionality and the shortcut for that is Alt+E. – user44 Aug 15 '13 at 14:25
3

You can edit /etc/nanorc to set it permanently (uncomment set undo). Note that under Mac you need to use esc|then|u to undo. – ishahak Jul 16 '19 at 07:10

score 8 · Answer 3 · answered Mar 02 '16 at 14:41

8

You can also add the line

set undo

in the .nanorc file. This enables the experimental undo feature on startup in versions below 2.4, such as 2.2.6 which seems to be the standard installation on many Linux distros.

answered Mar 02 '16 at 14:41

hueman

81

How to use Undo functionality in Nano?

3 Answers3

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