I haven't ever had to do anything serious in C but it's hard to imagine getting it 100% right.
A while back I wrote some C code to do the "short-bread" problem (it's a bit of a tradition at work to give it to people as their first task, though in Python it's a lot easier). Implementing a deque using all of the modern guard rails and a single file unit test framework still took me a lot of attempts.
A while back I wrote some C code to do the "short-bread" problem (it's a bit of a tradition at work to give it to people as their first task, though in Python it's a lot easier). Implementing a deque using all of the modern guard rails and a single file unit test framework still took me a lot of attempts.