.vimrc configuration file does not load when editing with 'sudo'

Question

I have problem with .vimrc file, the problem is that it sometimes get loaded, and sometimes not.

  1 set number
  2 syntax on
  3 set autoindent
  4 map <F2> :!g++ % -Wall -time -O<CR>
  5 echo "it works!"

I've added echo to check if it's loaded, and when I type e.g. vim .vimrc, it gets loaded and shows me "it works" in terminal, but when I type e.g. sudo vim test.cpp it doesn't get loaded, the message doesn't show up. I'm using debian.

Answer 1

When you use sudo, Vim gets launched under a different user (root). As this user has a different home directory, another ~/.vimrc is loaded (or none, if that user doesn't have one). You can solve the problem in multiple ways:

1. You can directly specify the location of your .vimrc: sudo vim -u $HOME/.vimrc (this won't help with plugins, though).
2. You can use sudo -e <file> or sudoedit.
3. You can symlink your .vimrc (and the .vim plugins directory) for root: sudo ln -s $HOME/.vimrc .vimrc; sudo ln -s $HOME/.vim .vim
4. You can change the entire home directory of root to be the same as yours (not recommended, because of security and access rights!)

Answer 2

sudo vim causes vim to be run as the root user. Which mean vim looks for the the vimrc in root's home directory and not yours.

The two choices you have to fix this are use

sudo -e <file>

Or copy your vim configuration to root's home directory.

sudo -e or sudoedit copies the file to a tmp directory and allows you to edit it and then copies it back on save. This is safer than using sudo vim and is the recommended way of solving this problem.