PM_SCANNING
if (scanp->ps_scan_flags & PM_SCANNING) {
scanp->ps_scan_flags |= PM_SCANNING;
ASSERT(scanp->ps_scan_flags & PM_SCANNING);
scanp->ps_scan_flags &= ~PM_SCANNING;
while (scanp->ps_scan_flags & (PM_SCANNING | PM_SCAN_DISPATCHED)) {
(PM_SCANNING | PM_SCAN_DISPATCHED | PM_SCAN_AGAIN)));
if (scanp->ps_scan_flags & PM_SCANNING) {