Re: [boost] Thread cancellation

From: Anthony Williams (anthony_w.geo_at_[hidden])
Date: 2007-11-02 10:25:32

Beman Dawes <bdawes_at_[hidden]> writes:

> Anthony Williams wrote:
>> Howard Hinnant <howard.hinnant_at_[hidden]> writes:
>> 
>>> Here's an interesting read on the subject:
>>>
>>> http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2455.pdf
>>>
>>> For those of you not familiar with the language of standardization,  
>>> this is an official letter from the C committee to the C++ committee  
>>> saying: "Thank you for removing cancellation.  Now we want you to  
>>> promise that you will not even discuss bringing it back."
>> 
>> I just spotted that in the mailing. Ouch. I know we removed cancellation so we
>> could make progress on other stuff, but I really think we ought to bring it
>> back.
>> 
>> One of the key things people have said to me when I have mentioned that we're
>> standardizing a thread library for C++ is "does that include cancellation?"
>> Everyone I've spoken to about it has been very glad the answer was "yes."
>> 
>> I've added cancellation to the boost thread library (though currently
>> this_thread::cancellation_point is the only cancellation point on pthreads ---
>> something I intend to fix), and I don't intend to remove it.
>
> I think Boost will perform a valuable service to the community if we 
> develop successful cancellation extensions.

Thank you for the support. I have now extended the current thread library on
trunk so that it supports all the cancellation points from N2320 on POSIX and
Windows.

> The name, however, is very contentious, particularly among the POSIX 
> community. It appears to me that any C++ language or library use of the 
> name "cancellation" causes the POSIX community to try to derail all 
> further progress, regardless of technical merit or existing practice.
>
> I strongly suggest we use the name "interruption". That appears to be 
> much more acceptable.

I'll change the name over. It's just a name, after all.

Anthony
-- 
Anthony Williams
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