_LOCKOWNER
_LOCKOWNER(f) = NULL; \
if (_LOCKOWNER(fp) == thr_self()) {
while (_LOCKOWNER(fp) != NULL)
_LOCKOWNER(fp) = thr_self();
_LOCKOWNER(fp) = NULL;
if (_LOCKOWNER(fp) == thr_self()) {
} else if (_LOCKOWNER(fp) == NULL) {
_LOCKOWNER(fp) = thr_self();