M_RNG
*bufnext++ = M_RNG;
if ((*pat & M_MASK) == M_RNG) {
*bufnext++ = M_RNG;
if ((*pat & M_MASK) == M_RNG) {
*bufnext++ = M_RNG;
if ((*pat & M_MASK) == M_RNG) {
*bufnext++ = M_RNG;
if ((*pat & M_MASK) == M_RNG) {