Execute a command whenever Ubuntu starts

Question

I have Ubuntu 16.04. From here Run Scripts on Start UP. I followed this answer:

One approach is to add an @reboot cron task:

Running crontab -e will allow you to edit your cron. Adding a line like this to it:
@reboot /path/to/script
will execute that script once your computer boots up.

I was successfully able to edit file crontab.

but I couldn't be able to save it using:

:q
:wq
CTRL+x

None of them worked. I got this message on command :q:

No write since Last Change (add ! to override

After executing command - EDITOR=vi crontab -e

Output - no crontab for admin - using an empty one
Again on executing command - sudo EDITOR=vi crontab -e

Output - no crontab for root - using an empty one

Hi, @muru that is my point :wq exit the window but it not save cron file. — Utkarsh Dubey, Jun 08 '17 at 04:59
If that was your point, then say so in the question. What does crontab -l show after you edit and do :wq? — muru, Jun 08 '17 at 05:00
I mention this in my question:

:q

:wq

Ctrl+x

None of them are work. — Utkarsh Dubey, Jun 08 '17 at 05:05
"None of them are work" doesn't mean anything. What do you mean by that? You did say what happened when you did :q, but you said nothing of the others. Without knowing what you mean by that, sentences like that are ignored as garbage. — muru, Jun 08 '17 at 05:06
@george I get the impression that creating a cron job that causes a reboot may be ill-advised and beyond the current skill level of the OP. Unless the OP's user account is admin I'd be concerned as to what cron he is actually editing. Stuffing something like this in cron is probably not the best thing for an obviously novice user to be doing. — jones0610, Jun 08 '17 at 05:14
Is your editor vim or nano? If nano see update on my answer — George Udosen, Jun 08 '17 at 05:31
How come it comes preinstalled, use which nano to see if its there. It should be. — George Udosen, Jun 08 '17 at 05:34
Why are you using EDITOR=vi crontab -e please simply use crontab -e and let it use the default editor which I believe is nano — George Udosen, Jun 08 '17 at 05:40
Now that's strange, are you the original owner of the said system and did you remove it some how? — George Udosen, Jun 08 '17 at 05:44
No, I am not the original owner. It's a client machine. I don't know if he remove nano or not. — Utkarsh Dubey, Jun 08 '17 at 05:48

George Udosen · Accepted Answer · 2017-06-08T05:34:09.080

1

You have done well so far. The No write since Last Change(add ! to override) means you have written something and are closing without saving so the editor assumes you don't wish to save your changes and offers you the option of doing so with :q!. Now you need to use :wq to ensure that the changes are written then the editor is quit or exited.

Where its a nano editor as I noticed crontab uses this please do the following:

To save: Ctrl+o, then press Enter
To close: Ctrl+x

edited Jun 08 '17 at 05:34

answered Jun 08 '17 at 04:53

George Udosen

36,677

Hi, @George it shows Not an editor command :qw. – Utkarsh Dubey Jun 08 '17 at 04:55
Updated the answer, sorry syntax error – George Udosen Jun 08 '17 at 04:56
@UtkarshDubey its :wq not :qw – d a i s y Jun 08 '17 at 06:00
@daisy I spoke with OP and the issue is sudo privileges. The original owner of the system did some awful things and lost sudo powers and other so he OP has to fixed that first. – George Udosen Jun 08 '17 at 06:23
1

Okay sorry i didn't checked edited answer - Your comment syntax error is about :qw – d a i s y Jun 08 '17 at 06:27
1

Thanks a lot @George, It works perfectly on Client other Ubuntu machine which have nano installed. And for 1st machine may be there is something wrong in machine. – Utkarsh Dubey Jun 08 '17 at 06:31

score 0 · Answer 2 · answered Jun 08 '17 at 04:55

0

Having a cron job that causes an unexpected, immediate reboot could cause you frustration and confusion.

If you are convinced that you want to do this, the command to write and exit the editor depends on what editor you selected when you invoked the crontab -e command.

Esc :wq! or Shift ZZ will work for vi

For nano, Ctrl O followed by Ctrl X

answered Jun 08 '17 at 04:55

jones0610

2,157

Hi, @jones0610 How to invoke editor? – Utkarsh Dubey Jun 08 '17 at 05:02
@UtkarshDubey EDITOR=nano crontab -e – muru Jun 08 '17 at 05:04

Execute a command whenever Ubuntu starts

2 Answers2