shmctl_args
{ .sy_narg = AS(shmctl_args), .sy_call = (sy_call_t *)lkmressys, .sy_auevent = AUE_NULL, .sy_flags = 0, .sy_thrcnt = SY_THR_ABSENT }, /* 512 = shmctl */
struct shmctl_args *p = params;
sys_shmctl(struct thread *td, struct shmctl_args *uap)
int sys_shmctl(struct thread *, struct shmctl_args *);