[Python-Dev] Re: asyncore 2.1.1/2.2 incompatibility

[Carl J. Nobile]

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Hi all,

I've created two exceptions that will be raised when either a SIGTERM or SIGHUP
is caught. This seems to have solved the problem as the slightly modified
version of my test server, that I've attached, demonstrates. This is a much
more elegant solution to the problem, but I'm still not so sure that the poll
functions should be ignoring EINTR in the way that they do. I wonder how much
code this has broken?

At a minimum something should be said about how this works and how to handle
signals in the asyncore documentation.

Thanks for all your help.

Carl

On 22-Mar-2002 Andrew Kuchling wrote:
> On Fri, Mar 22, 2002 at 01:05:28PM -0500, Guido van Rossum wrote:
>>> program to re-read its configuration file.  This works in 2.2.1
>>                                                            ^^^^^
>>I presume you mean 2.1.1?  From the CVS log it looks like this has
> 
> 2.1.1 is correct; typo on my part.
> 
>>I think if Carl (who submitted 528295) had created a signal handler
>>that raised an exception (rather than simply return), that would
>>probably have had the desired effect -- but I'm not 100% sure.  If it
>>works, it has the added advantage of working with earlier versions of
>>Python too.  I'd like to hear if this workaround works.  Carl?
> 
> Trying it, it looks like it does, and a quick glance at ceval.c agrees.
> The docs for libsignal don't mention anything about what happens when
> you raise an exception in a signal handler, though, and perhaps they
> should.  
> 
> To sum up, it looks like this isn't a bug, and the test program should
> be raising a RereadConfiguration exception instead of relying on
> details of asyncore's loop.  That also means asyncore doesn't need a
> way to be told to exit its loop, since raising an exception does the
> job nicely and Pythonically.
> 
> --amk                                                            
> (www.amk.ca)
> One has no wish to be devoured by alien monstrosities, even in the
> cause of political progress.
>     -- One of the Tribunal, in "Carnival of Monsters"

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E-Mail: Carl J. Nobile <cnobile1@twcny.rr.com>  Home
E-Mail: Carl J. Nobile <cnobile@AppliedTheory.com>  Work
Date: 22-Mar-2002
Time: 21:45:55
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