chmod not working in a non super user

Question

I have created a file named *.txt in /home using following command:

sudo nano *.txt

Then I have changed owner of *.txt to a user that I've created:

sudo useradd -c "ABC"

sudo chown ABC *.txt

I login to ABC by typing:

sudo login ABC

I tried to change permission of the file:

sudo chmod 777 *.txt

This is the result:

ABC is not in the sudoers file. This incident will be reported.

Permissions have successfully changed when running chmod from the original user: batman.

How can I change the permissions of *.txt from the new owner?

Solution

All I need to do is to be in the directory which contains the file. Solution:

cd home

chmod 777 *.txt

That's all. But be aware to change the name of the file because the * in *.txt isn't a valid name.

Comments

[Andrea Corbellini]

1. please copy & paste output instead of screenshots; 2. to use sudo in Ubuntu you need to be in the sudo group (or you need to be in the sudoers file like the error suggests); 3. you're getting "no such file or directory" because you forgot to cd to the right directory

[Johny Nassar]

What's the right directory? It should be in ABC user, right?

[Andrea Corbellini]

No, you created the files in your home directory, they can't be in ABC's home directory: cd ~batman; chmod 744 *.txt -- but you may get errors depending on the directory permissions

[Johny Nassar]

I'm new to Ubuntu so I don't get it 100% the group idea. Sorry.

[Johny Nassar]

But the ABC user is the new owner of this file. Right? How can I fix it ?

[Johny Nassar]

@AndreaCorbellini I didn't understand, plz could you explain more

[Johny Nassar]

I have some questions: 1. How can I make a home directory for ABC. 2. When I make a chmod, It's obligatory that I must go to the file location? 3.When I tried to chmod in the batman it's successfully completed and there's no problem with that!! Why? Thanks.