__NFDBITS          60 sys/select.h   	__fd_mask fds_bits[__howmany(FD_SETSIZE, __NFDBITS)];
__NFDBITS          64 sys/select.h   	((p)->fds_bits[(n) / __NFDBITS] |= (1 << ((n) % __NFDBITS)))
__NFDBITS          66 sys/select.h   	((p)->fds_bits[(n) / __NFDBITS] &= ~(1 << ((n) % __NFDBITS)))
__NFDBITS          68 sys/select.h   	((p)->fds_bits[(n) / __NFDBITS] & (1 << ((n) % __NFDBITS)))
__NFDBITS          80 sys/select.h   #define NFDBITS	__NFDBITS