Embedded processor projects usually have an infinite loop, so they perform their job as long as power is applied.
"1u" means nothing more that "Take the constant number 1 as an unsigned int"
Because any value except 0 (zero) has the meaning of "true" in C-language the statement
is the infinite loop.
I (personally dislike this writing. I use
#define forever 1
which is quite more readable.
Thanks a lot! That makes sense. As I noted, I thought it was a returned value and it isn't. This shows how important it is to comment code clearly.