ktr_genio
struct ktr_genio ktg;
kth.ktr_len = (int)sizeof(struct ktr_genio);
ktrgenio((struct ktr_genio *)m, ktrlen);
static void ktrgenio(struct ktr_genio *, int);
ktrgenio(struct ktr_genio *ktr, int len)
int datalen = len - sizeof (struct ktr_genio);
char *dp = (char *)ktr + sizeof (struct ktr_genio);