[Python-bugs-list] [Bug #114780] Rare hangs in w9xpopen.exe

[noreply@sourceforge.net]

Bug #114780, was updated on 2000-Sep-19 01:50
Here is a current snapshot of the bug.

Project: Python
Category: Windows
Status: Closed
Resolution: Wont Fix
Bug Group: 3rd Party
Priority: 1
Submitted by: tim_one
Assigned to : mhammond
Summary: Rare hangs in w9xpopen.exe

Details: Every two or three days, when I'm running the std test suite on my
Win98SE box, test_popen2 just hangs.  wintop shows that w9xpopen.exe is
alive, but not consuming any cycles.  test_popen2.py is waiting on a
.read().

No other clues.  It *may* be the case that I'm establishing a modem
connection near the time test_popen2 starts to run.  I'll try to provoke
that.

Assigned to MarkH simply to share the misery <wink>.  Mark, I don't expect
you to "fix this", but I don't expect me to either -- it's just something
we should both be aware of.


Follow-Ups:

Date: 2001-Jan-12 10:15
By: tim_one

Comment:
Closed as WontFix and 3rdParty, as there's no reason to believe we're
missing anything we can fix.  I still see hangs once or twice a week (here
and in DevStudio).  My only guess was that these may have coincided with
establishing phone-modem connections, but I didn't get anywhere with that,
and now that I have an "always on" cable modem instead there's no change in
symtpoms or frequency.  Smells like an OS bug.

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Date: 2000-Oct-04 18:53
By: tim_one

Comment:
A (useless, alas) clue:  every now & again, doing a Batch Build under MSVC
hangs in midstream:  Never makes progress, and Stop Build has no effect. 
Have to kill DevStudio via the task manager.  Then things get *really*
screwed up unless I also kill a leftover "vcspawn" task from the task
manager.  This suggests that Win98SE (or, at least, my copy of it) simply
screws up spawning from time to time.  I reduced the priority on this bug
again, reflecting that I now suspect it's a platform bug we're not causing
and can't cure.
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Date: 2000-Sep-25 15:07
By: tim_one

Comment:
Just noting that I've been building and testing Python a *lot* since I
entered this bug report, and haven't seen the problem again.
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Date: 2000-Sep-19 05:51
By: gvanrossum

Comment:
Tim, do you remember the problem I had with using popen() from IDLE? I had
code that essentially did os.popen("start "+url).close(). This worked fine
in a DOS box but hung inexplicably for 30 seconds before returning and
starting the browser when used in IDLE. The problem went away (the call
returned immediately and the browser was started within 2-3 seconds) when I
saved the pipe object in an instance variable. We never fixed this, but I
tracked it down to probably something having to do with the need to pump
events. Mark will understand. I don't doubt that popen2, popen3, popen4 all
share this problem. (Check webbrowser.py, class WindowsDefault, for the
current solution.)
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For detailed info, follow this link:
http://sourceforge.net/bugs/?func=detailbug&bug_id=114780&group_id=5470