Re: [boost] [thread] [rfc] patch to change condition_variable and mutex error checks

Subject: Re: [boost] [thread] [rfc] patch to change condition_variable and mutex error checks
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2011-12-02 15:21:45

Le 02/12/11 16:54, Brett Lentz a écrit :
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> On 11/30/2011 06:21 PM, Vicente J. Botet Escriba wrote:
>> Le 30/11/11 23:05, Brett Lentz a écrit :
>>> On 11/30/2011 04:51 PM, Peter Dimov wrote:
>>>> Brett Lentz wrote:
>>>>> Patch is attached.
>>>>>
>>>>> I'd like to get some comments about this patch. Does it seem
>>>>> reasonable enough to accept? Is there a better way to handle
>>>>> it?
>>>>>
>>>>> BOOST_VERIFY aborts on EINTR, but EINTR is usually not fatal,
>>>>> it just means you need to try later.
>>>> You've attached the wrong patch. Anyway, POSIX specifically
>>>> forbids pthread functions from returning EINTR.
>>>>
>> I wasn't aware of this.
>>> DOH!  Correct patch attached here.
>>>
>>> Posix may forbid it, but that doesn't necessarily stop a broken
>>> implementation from doing it. Like the original e-mail said, this
>>> was a result of an actual customer's experience in an actual
>>> production situation.
>> I agree that this should be managed by Boost.Thread as other
>> workarounds. As many others we have been forced to use this idiom
>> since a long time. Even if the patch is not too much time consuming
>> it could use conditional compilation and be included only on bad
>> posix implementations.
>>> While I'd like to see the patch accepted, it would be equally
>>> valid to just say that it's not a problem boost should be
>>> solving, and that I need to file a bug with the OS vendor that
>>> they shouldn't be violating POSIX like this. ;-)
>> Yes, please.
>>
>> Best, Vicente
>>
> I've created ticket #6200 for this patch.
>
>

This part is not correct

         55	res=pthread_cond_wait(&cond,&internal_mutex);

          55	int ret;
          56	do {
          57	  ret = pthread_cond_wait(&cond,m.mutex()->native_handle());
          58	} while (ret == EINTR);

Note that before the mutex used was internal_mutex. Are you sure that 
this patch is working for your applications?

https://svn.boost.org/trac/boost/ticket/6200#comment:1

Best,
Vicente