Auto-indent spaces with C in vim?

These two commands should do it:

:set autoindent:set cindent

For bonus points put them in a file named .vimrc located in your home directory on linux

I wrote all about tabs in vim, which gives a few interesting things you didn't ask about. To automatically indent braces, use:

:set cindent

To indent two spaces (instead of one tab of eight spaces, the vim default):

:set shiftwidth=2

To keep vim from converting eight spaces into tabs:

:set expandtab

If you ever want to change the indentation of a block of text, use < and >. I usually use this in conjunction with block-select mode (v, select a block of text, < or >).

(I'd try to talk you out of using two-space indentation, since I (and most other people) find it hard to read, but that's another discussion.)

A lot of vim's features (like autoindent and cindent) are turned off by default. To really see what vim can do for you, you need a decent ~/.vimrc.

A good starter one is in $VIMRUNTIME/vimrc_example.vim. If you want to try it out, use

:source $VIMRUNTIME/vimrc_example.vim

when in vim.

I'd actually suggest just copying the contents to your ~/.vimrc as it's well commented, and a good place to start learning how to use vim. You can do this by

:e $VIMRUNTIME/vimrc_example.vim:w! ~/.vimrc

This will overwrite your current ~/.vimrc, but if all you have in there is the indent settings Davr suggested, I wouldn't sweat it, as the example vimrc will take care of that for you as well. For a complete walkthrough of the example, and what it does for you, see :help vimrc-intro.