PIPE_SEL 255 kern/sys_pipe.c if (cpipe->pipe_state & PIPE_SEL) { PIPE_SEL 256 kern/sys_pipe.c cpipe->pipe_state &= ~PIPE_SEL; PIPE_SEL 666 kern/sys_pipe.c rpipe->pipe_state |= PIPE_SEL; PIPE_SEL 670 kern/sys_pipe.c wpipe->pipe_state |= PIPE_SEL;