Re: [boost] Re: Windows MSVC thread exit handler for staticly linked Boost.Thread

From: Aaron W. LaFramboise (aaronrabiddog51_at_[hidden])
Date: 2004-08-02 16:08:36

Michael Glassford wrote:
> Aaron W. LaFramboise wrote:
>>Michael Glassford wrote:
>>>Aaron W. LaFramboise wrote:
>>>>Following is an implementation of, and some comments on, a staticly
>>>>linked Boost.Thread thread exit handler for MSVC.
>>>>
>>>>By the way, I appologize for talking so long to cough this up after
>>>>posting teasing remarks about this months ago.  Programming is presently
>>>>a hobby and volunteer work for me, unfortunately.
>>>
>>>Thanks! I've been looking forward to you posting this, and it appears to 
>>>work beautifully for VC++ 7.1 (as others have already commented). Do I 
>>>have your permission to included it in Boost.Threads under the Boost 
>>>license (with your name on it, of course)?
>>
>>Yes, you and anyone else have perpetual permission to offer it under any
>>license you choose.
> 
> Thank you. It's in, and will be in the upcoming release. A lot of people 
> will be happy, including me! I look forward to the GCC version as well, 
> though I haven't yet used GCC myself.

Make sure you look at Roland's code that gets MSVC6 right by doing a
fixup that fixes a problem in the TLS support code.  That fixup should
only be done on MSVC6 though.

For GCC/MinGW, I'm actually adding an API that gets all of this right:
an atexit variant that knows about module unloading and thread
destruction.  Ideally all compilers would have such an API to make these
sorts of problems easy. :)

> If I understand what DLL_PROCESS_DETACH means (the thread is being 
> notified that it is being detached because the  process is exiting), the 
> call to on_process_exit() is incorrect; on_process_exit() is meant to be 
> called when the process actually exits (it calls TlsFree()). The most 
> likely place to call it is at the end of main() or after the main thread 
> exits.

Well, as near as I can tell, when the TLS routine is called with
DLL_PROCESS_DETACH, this will be the absolute last user code executing
in the process, including DLL destructors.  As far as I know, once you
return from DLL_PROCESS_DETACH in the TLS routine, no more user code
will run.

Aaron W. LaFramboise