mk4
mk4(bsbpb->hid, bpb.hid);
mk4(bsbpb->bsec, bpb.bsec);
mk4(bsxbpb->bspf, bpb.bspf);
mk4(bsxbpb->rdcl, bpb.rdcl);
mk4(bsx->volid, x);
mk4(img, 0x41615252);
mk4(img + MINBPS - 28, 0x61417272);
mk4(img + MINBPS - 24, 0xffffffff);
mk4(img + MINBPS - 20, 0xffffffff);
mk4(bsbpb->hid, bpb.hid);
mk4(bsbpb->bsec, bpb.bsec);
mk4(bsxbpb->bspf, bpb.bspf);
mk4(bsxbpb->rdcl, bpb.rdcl);
mk4(bsx->volid, x);
mk4(img, 0x41615252);
mk4(img + MINBPS - 28, 0x61417272);
mk4(img + MINBPS - 24, 0xffffffff);
mk4(img + MINBPS - 20, 0xffffffff);