[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: Core
Status: Open
Resolution: None
Bug Group: Platform-specific
Priority: 2
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: 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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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-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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For detailed info, follow this link:
http://sourceforge.net/bugs/?func=detailbug&bug_id=114780&group_id=5470