ecpp_regs
mcopyin(mp, NULL, sizeof (struct ecpp_regs), NULL);
struct ecpp_regs rg;
struct ecpp_regs *rg;
rg = (struct ecpp_regs *)mp->b_cont->b_rptr;
#define ECPPIOC_SETREGS _IOW('p', 73, struct ecpp_regs)
#define ECPPIOC_GETREGS _IOR('p', 74, struct ecpp_regs)
_NOTE(SCHEME_PROTECTS_DATA("unique per call", ecpp_regs))
struct ecpp_regs regs; /* control/status registers */