Dear friends,

I'm completely new to using Linux and I'll probably ask the most stupid question ever, but I didn't manage to find the answer on the network, so here it is:

I'm modifying the network config file on a Ubuntu server system using the command line. I altered the file but I don't know how to save it. When I press the ctrl + x keyboard combination I get this message at the bottom of the screen:

-- X^ mode (^]^D^E^F^I^K^L^N^O^Ps^U^V^Y)

... and I'm kind of stuck at that screen. Please help!

It seems you are using the vi editor instead of nano.

In nano you can save using Ctrl+x, but this shortcut does something else in vi.

To save a file in vi, first press the Escape button to leave insert mode.

Then type the following to, respectively, enter Command-line mode and save and exit the file:
If the file has read-only permissions, you will have to add an exclamation mark to force the file to be saved and exit:
Vi might come off as a bit of a strange editor, and takes some time to get used to, but once you start to get the hang of it, it's really nice.

You can find a lot of beginner tutorials on the internet.

PS. If it's a system file you are trying to edit, you will probably also require superuser permissions to edit it.

Thank you so much, Man! You made my evening

Actually, that's a bit cargo cult. To exit & save in vi/vim, its just
w = write
q = quit no save
x = exit with save
! = do it, even if its a read only file