O_NLDELAY
#define NLDELAY O_NLDELAY
if ((csp->t_flags & O_NLDELAY) == O_NL1)
if ((csp->t_flags & O_NLDELAY) == O_NL2)
#define NLDELAY O_NLDELAY
(O_NLDELAY|O_TBDELAY|O_CRDELAY|O_VTDELAY|O_BSDELAY)