nekto@darkstar:~/workspace/py3k$ /usr/bin/time ./python test_listdir.py
0.61user 1.18system 0:24.44elapsed 7%CPU (0avgtext+0avgdata 258688maxresident)k
42424inputs+0outputs (26major+16312minor)pagefaults 0swaps

nekto@darkstar:~/workspace/py3k$ /usr/bin/time ./python test_listdir.py
0.39user 0.48system 0:00.87elapsed 99%CPU (0avgtext+0avgdata 258688maxresident)k
0inputs+0outputs (0major+16338minor)pagefaults 0swaps


nekto@darkstar:~/workspace/py3k$ /usr/bin/time ./python test_xlistdir.py
0.66user 1.10system 0:24.69elapsed 7%CPU (0avgtext+0avgdata 25568maxresident)k
42424inputs+0outputs (26major+1731minor)pagefaults 0swaps

nekto@darkstar:~/workspace/py3k$ /usr/bin/time ./python test_xlistdir.py
0.34user 0.43system 0:00.78elapsed 98%CPU (0avgtext+0avgdata 25568maxresident)k
0inputs+0outputs (0major+1758minor)pagefaults 0swaps


nekto@darkstar:~/workspace/py3k$ cat test_xlistdir.py
import os

os.chdir('/tmp')
for i in os.xlistdir('.'):
    len(i)


nekto@darkstar:~/workspace/py3k$ ls /tmp | wc -l
712205