[ python-Bugs-756940 ] can't CNTRL-C when running os.system in a thread

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Bugs item #756940, was opened at 2003-06-18 20:52
Message generated for change (Comment added) made by facundobatista
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https://sourceforge.net/tracker/?func=detail&atid=105470&aid=756940&group_id=5470

Category: Threads
Group: Python 2.2.2
Status: Open
Resolution: None
Priority: 5
Submitted By: Greg Jones (morngnstar)
Assigned to: Nobody/Anonymous (nobody)
Summary: can't CNTRL-C when running os.system in a thread

Initial Comment:
This is related to Bug #756924.

When os.system is called in a thread, Control-C is 
ignored.

Steps to reproduce:
1. Download the attached file fibonacci.py.
2. Run python2.2 fibonacci.py.
3. Hit CNTRL-C.

fibonacci.py starts a thread that executes fibonacci.py 
again (but with a flag to prevent this from recursing 
infinitely). Then it computes and prints the Fibonacci 
sequence, the slow way. The process executed in the 
thread redirects this to a file to avoid conflict over 
stdout. All this is just to give the program something to 
do while you hit CNTRL-C.

Expected, and Python 2.1 behavior:
You get a KeyboardInterrupt exception, a stack trace, 
and the program exits.

Actual Python 2.2 behavior:
No response. You have to run kill on the process.

Maybe this is not a bug, but rather a limitation of Linux, 
since I understand SIGINT is blocked during the C 
function 'system'. However, CNTRL-C worked in Python 
2.1, and that was nicer.


Removing the lines of code described in Bug #756924 
also fix this bug.

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>Comment By: Facundo Batista (facundobatista)
Date: 2005-01-15 16:23

Message:
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The other bug have a very long discussion about this, and
talks about patches to be applied to Py2.4, and the last
patch is actually accepted. Maybe this is already fixed,
please give it a try.

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Comment By: Facundo Batista (facundobatista)
Date: 2005-01-15 16:23

Message:
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Please, could you verify if this problem persists in Python 2.3.4
or 2.4?

If yes, in which version? Can you provide a test case?

If the problem is solved, from which version?

Note that if you fail to answer in one month, I'll close this bug
as "Won't fix".

Thank you! 

.    Facundo

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Comment By: Greg Jones (morngnstar)
Date: 2003-06-18 23:58

Message:
Logged In: YES 
user_id=554883

OS is Linux.

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You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=756940&group_id=5470