[Python-bugs-list] select module: Bug in select.select() (PR#365)
r32813@email.sps.mot.com
r32813@email.sps.mot.com
Thu, 22 Jun 2000 22:03:44 -0400 (EDT)
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Hi Guido,
Below is the dbx information from the coredump. This only occurs when the
select.select() function is used within a thread. This same error occurs on
both Python 1.5.1 and Python 1.5.2 when AIX 4.3.1. This problem does not
occur on AIX 4.1.4.
$ dbx -I ./Modules ./python core
Type 'help' for help.
reading symbolic information ...
[using memory image in core]
Segmentation fault in initselect at line 235 in file "Modules/selectmodule.c"
($t2)
235 PyObject *tout = Py_None;
We have been able to reproduce the coredump by modifying the test_select.py
to perform the test within a thread. Attached is the modified file called
test_thread_select.py. Just place this file in the Lib/test directory to see
this problem.
Thanks for all your help.
Regards,
Wah Meng
Guido van Rossum wrote:
> > The python 1.5.2 built on AIX 4.3.1.0 platform created a coredump when
> > this command was run:-
> >
> > select.select(waitList, [], [], timeWait)
> >
> > This command worked fine in Python 1.5.1 build and also fine on Python
> > 1.5.2 built on HP 10.2. It just didn't work in AIX 4.3.1.0 build on
> > 2 AIX machines that we have.
>
> Could you give us some more information? You're indicating that it's
> platform specific; we don't have an AIX box. I'm guessing it's not
> obvious that our code is wrong, but it may violate some guidelines
> given by AIX manuals. If we ever want to fix this, we'll need to
> interact with you. the first thing we need is a decent stack trace;
> we'll take it from there.
>
> If you could investigate this on your own and come up with a fix, that
> would probably the best solution...
>
> --Guido van Rossum (home page: http://www.python.org/~guido/)
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Hi Guido,
<p>Below is the dbx information from the coredump. This only occurs when
the select.select() function is used within a thread. This same error occurs
on both Python 1.5.1 and Python 1.5.2 when AIX 4.3.1. This problem does
not occur on AIX 4.1.4.
<p><tt>$ dbx -I ./Modules ./python core</tt>
<br><tt>Type 'help' for help.</tt>
<br><tt>reading symbolic information ...</tt>
<br><tt>[using memory image in core]</tt><tt></tt>
<p><tt>Segmentation fault in initselect at line 235 in file "Modules/selectmodule.c"
($t2)</tt>
<br><tt> 235
PyObject *tout = Py_None;</tt>
<p>We have been able to reproduce the coredump by modifying the test_select.py
to perform the test within a thread. Attached is the modified file called
test_thread_select.py. Just place this file in the Lib/test directory to
see this problem.
<p>Thanks for all your help.
<p>Regards,
<br>Wah Meng
<p>Guido van Rossum wrote:
<blockquote TYPE=CITE>> The python 1.5.2 built on AIX 4.3.1.0 platform
created a coredump when
<br>> this command was run:-
<br>>
<br>> select.select(waitList,
[], [], timeWait)
<br>>
<br>> This command worked fine in Python 1.5.1 build and also fine
on Python
<br>> 1.5.2 built on HP 10.2. It just didn't work in AIX 4.3.1.0
build on
<br>> 2 AIX machines that we have.
<p>Could you give us some more information? You're indicating that
it's
<br>platform specific; we don't have an AIX box. I'm guessing it's
not
<br>obvious that our code is wrong, but it may violate some guidelines
<br>given by AIX manuals. If we ever want to fix this, we'll need
to
<br>interact with you. the first thing we need is a decent stack
trace;
<br>we'll take it from there.
<p>If you could investigate this on your own and come up with a fix, that
<br>would probably the best solution...
<p>--Guido van Rossum (home page: <a href="http://www.python.org/~guido/">http://www.python.org/~guido/</a>)</blockquote>
</html>
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