The below defines a new function.
A common convention, used in FreeBSD is to define it like this.
At the beginning of my programming career, I used the first definition. Later on, I used the second. The advantage of the second definition, is that you can do this
grep ^f foo.c
or in VIM /^foo
Using regular expressions to find the function definition, as opposed to its use or declaration is very useful. This is the reason why I always use this convention of defining functions.