Bugs item #1703448, was opened at 2007-04-19 03:22
Message generated for change (Settings changed) made by rhettinger
You can respond by visiting:
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1703448&group_id=5470
Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: Python Library
Group: Python 2.5
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Andrew Bennetts (spiv)
>Assigned to: Raymond Hettinger (rhettinger)
Summary: "t.join(); assert t not in threading.enumerate()" fails
Initial Comment:
This script always fails for me, usually on the very first iteration:
----
import threading
while True:
print '.',
t = threading.Thread(target=lambda: None)
t.start()
t.join()
alive_threads = threading.enumerate()
assert len(alive_threads) == 1, alive_threads
----
The docs clearly say this is expected to work: Thread.join is described as
"Wait until the thread terminates" and threading.enumerate's description says
it will "Return a list of all currently active Thread objects ... It excludes
terminated threads". So by the time t.join() returns, the thread should not be
reported by threading.enumerate anymore.
The bug appears to be that while the thread is shutting down, join() may exit
too early: it waits for the __stopped flag to be set, but the thread hasn't
necessarily been removed from the _active dict by that time, so enumerate will
report a "stopped" thread. (Or if you like the bug is that __stopped is can be
set while the thread is still in the _active dict.)
A workaround is to filter the results of threading.enumerate() through [t for t
in threading.enumerate() if t.isAlive()].
----------------------------------------------------------------------
You can respond by visiting:
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1703448&group_id=5470
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
