Yeah, I'm also going to just add 1usec. As I don't increment by 1usec anyway. I try to increment to the next event that will occur to make it more efficient. I mean your method sounds pretty good, as it does just seem to add 1usec each time for a syscall, which doesn't work so well with the underlying logic. And yeah, I also use mod. I mean we can use math.h, but I think ceil() is already a function without it. But yeah, mod is nicer. Depending on how you're doing it (like I multiply the data by 1000000 to get it to work properly), you may need to use long long ints just in case to prevent overflow.