highlight function names in c code

" Highlight all function names
syntax match cCustomFunc /\w\+\s*(/me=e-1,he=e-1
highlight def link cCustomFunc Function

To use this, put it in ~/.vim/after/syntax/c/highlight_functions.vim. (All files in ~/.vim/after/syntax/[filetype]/ will be sourced when vim opens a file of type [filetype].)