ECPP_IDLE
pp->e_busy = ECPP_IDLE;
while (pp->e_busy != ECPP_IDLE || qsize(WR(q))) {
if (pp->e_busy == ECPP_IDLE) {
if (pp->e_busy == ECPP_IDLE) {
pp->e_busy = ECPP_IDLE;
if (pp->e_busy != ECPP_IDLE) {
if (pp->e_busy == ECPP_IDLE) {
case ECPP_IDLE:
pp->e_busy = ECPP_IDLE;
pp->e_busy = ECPP_IDLE;
pp->e_busy = ECPP_IDLE;
pp->e_busy = ECPP_IDLE;
pp->e_busy = ECPP_IDLE;