> On Wed, Oct 10, 2012 at 6:18 AM, Ulrich Eckhardt
>> The comment clearly states "owned by current thread", not "owned by any
>> thread". The latter would also be useless, as that can change concurrently
>> at any time when owned by a different thread, so making decisions on this
>> state is futile.
Agree.
On Wed, Oct 10, 2012 at 12:21 PM, Ian Kelly <ian.g.ke...@gmail.com> wrote:
> Can you demonstrate an API bug that is caused by this?
A simple demo of this error is:
-----------8<------------------------8<----------------------
import time
from threading import Condition, Lock, Thread
cv = Condition(Lock())
def do_acquire():
cv.acquire()
print "cv acquired in thread"
time.sleep(5)
cv.release()
print "cv released in thread"
thread = Thread(target=do_acquire)
thread.start()
for i in range(10):
print "in main cv._is_owned: ", cv._is_owned()
time.sleep(1)
-----------8<------------------------8<----------------------
The condition variable is only acquired in the thread, so in main it should
always print false. However, my output gives:
$ python test.py
cv acquired in threadin main cv._is_owned:
True
in main cv._is_owned: True
in main cv._is_owned: True
in main cv._is_owned: True
in main cv._is_owned: True
cv released in thread
in main cv._is_owned: False
in main cv._is_owned: False
in main cv._is_owned: False
in main cv._is_owned: False
in main cv._is_owned: False
However, as long as you follow the generic pattern, i.e. always use
acquire() before wait(), this error is not triggered.
Thanks all.
Wenhua
--
http://mail.python.org/mailman/listinfo/python-list
