#define rwoff1 (write_off - read_off >= 0)
#define rwoff2 (write_off - read_off < HALF_UCHAR)

#define wcsum1 (write_off - _commit_sum >= 0)
#define wcsum2 (write_off - _commit_sum < HALF_UCHAR)

#define buffer_large_enough (NUMPROCS + NUMSWITCH <= BUFSIZE)
#define have_events_lost (events_lost != 0)