// parallelSleep returns the absolute difference between the start time
// of the two sleeps.
func parallelSleep(n int) int64 {
t := int64(C.twoSleep(C.int(n))) - <-sleepDone
if t < 0 {
return -t
}
return t
}
func parallelSleep(n int) {
C.twoSleep(C.int(n))
<-sleepDone
}