void add_stat_cache_entry(const char *path, struct stat *st) {
if(foreground)
cout << " add_stat_cache_entry[path=" << path << "]" << endl;
if(stat_cache.size() > max_stat_cache_size)
truncate_stat_cache();
pthread_mutex_lock(&stat_cache_lock);
stat_cache[path].stbuf = *st;
pthread_mutex_unlock(&stat_cache_lock);
}