grphdr
struct grphdr *grh;
grh = (struct grphdr *)&rpt[1];
grh = (struct grphdr *)((uint8_t *)src + auxlen);
grphdra_t *grphdr;
grphdr = (grphdra_t *)&(igmp3ra[1]);
grphdr->grphdra_type = rp->mrec_type;
grphdr->grphdra_numsrc = htons(rp->mrec_srcs.sl_numsrc);
grphdr->grphdra_group = V4_PART_OF_V6(rp->mrec_group);
src_array = (ipaddr_t *)&(grphdr[1]);
grphdr = (grphdra_t *)&(src_array[j]);