I mostly follow the 0, 1, N rule myself. The second time the code is needed I start looking into making the snippet a function and there's no doubt of doing tha

I mostly follow the 0, 1, N rule myself. The second time the code is needed I start looking into making the snippet a function and there's no doubt of doing that on the third account. The reason I do it is having several small functions gives the program a custom language. So I can effectively start programming in my own semantic terms even if I was writing C. Building high-level constructs is easier in high-level languages, of course, but you'll always have to start with the lowest building blocks and even that helps regardless of the language! The small functions will be marked for inlining and practically also inlined anyway so there's no performance cost. But it's immensely more practical to hypothetically write: const size_t len = get_data_size(fragment); rather than: const size_t len = ((struct packet_header *)&fragment->databuf[4])->sz + fragment->offset; The latter one is easy too because you know the code but you will have forgotten a year later.