Let's suppose I want to "protect" this code about being used without attribution, patenting it, or through any open source licence...

#include<stdio.h>
int main (void)
{     
  int version=2;

  printf("\r\n.Hello world, ver:(%d).", version); 

  return 0;
}

It's a little obvious or just a language definition example..

When a source stop being "trivial, banal, commonplace, obvious", and start to be something that you may claim "rights"?

Perhaps it depends on who read it, something that could be great geniality for someone that have never programmed, could be just obvious for an expert.

It's easy when watching two sources there are 10000 same lines of code, that's a theft.. but that's not always so obvious. How to measure amount of "ownness", it's about creativity? line numbers? complexity?

I can't imagine objetive answers for that, only some patches. For example perhaps the complexity, It's not fair to replace "years of engeneering" with "copy and paste". But is there any objetive index for objetive determination of this subject?

(In a funny way I imagine this criterion: If the licence is longer than the code, then there is no owner, just to punish not caring storage space and world resources =P)