Problem with vim when logged in as root

Question

When I login as root or edit a file by sudo mode all of the options in my /etc/vimrc are not working (e.g. highlight line-number etc.)

Answer 1

I guess the reason is that your home directory ~ is changed, where contains vim configuration file .vimrc .

Normally ~ is /root if you login as root, and is /home/YOURNAME if you login as YOURNAME.

Answer 2

Which vimrc are you talking about? I don't use/know vim, but in many cases rc files have two kinds of "incarnation": a system-wide rc-file under /etc that dictates the system defaults for the application and user-wide rc-files under the user homedirs, where users set their own settings, that override the defaults from the system-wide configuration file.

Meanwhile, there is sudo, that runs a program as another user (usually root, maybe, like su, it allows you to impersonate users other than root).

As you're running vim through sudo, my guess is that you're expecting ~/.vimrc to be something that it isn't. Either that, or you don't understand what is sudo doing when you invoke it.

If it really is ~/.vimrc, then it's not "not working", it's actually working quite well, the issue is that there's probably no ~root/.vimrc, or it exists with different settings than these you were expecting.