Consensus on MT-, AS- and AC-Safety docs.

[Carlos O'Donell]

On 12/04/2013 05:50 AM, Florian Weimer wrote:
> On 12/03/2013 04:27 PM, Carlos O'Donell wrote:
> 
>> I think that's certainly the right start. File a defect with the
>> Austin Group tracker and ask them the following things:
>>
>> * What if any unintended consequences could there be if the
>>    implementation choose to save and restore errno during
>>    signal handling?
>>
>> * Was it ever POSIX's intent to allow a signal handler to
>>    modify the errno of the interrupted code sequence or was
>>    that simply a consequence of being a signal handler and
>>    modifying global state?
>>
>> ... and anything else you think we should get an expert opinion
>> on before embarking upon a change like this.
> 
> Okay, I tried to summarize the previous discussion there:
> 
> <http://austingroupbugs.net/view.php?id=807>

Interesting response from Geoff Clare:

"If we make any change as a result of this issue, I think it should
just be to make it explicit that implementations are allowed, but
not required, to restore errno on return from signal handlers."

Which would be a nice addition and clarification to the standard.

Good work! Keep pushing this forward and we might kill a whole class
of ugly bugs :-)

Cheers,
Carlos.