Question

I regularly run into C-codes without folding. It is irritating to read them if there is no folding, particularly with long files. How can I fold them?

Answer 1

To fold according to syntax

:set foldmethod=syntax 

If you want to do it manually on the bits you want to fold away

:set foldmethod=manual 

then create new folds by selecting / moving and pressing zf e.g.

shift-v j j zf 

(ignoring the spaces)

Edit: Also see the comments of this answer for indent and marker foldmethods.