preadv_args
{ .sy_narg = AS(preadv_args), .sy_call = (sy_call_t *)sys_preadv, .sy_auevent = AUE_PREADV, .sy_flags = SYF_CAPENABLED, .sy_thrcnt = SY_THR_STATIC }, /* 289 = preadv */
sys_preadv(struct thread *td, struct preadv_args *uap)
struct preadv_args *p = params;
int sys_preadv(struct thread *, struct preadv_args *);