Re: [boost] Re: Re: Thread lib (good reason for static)

From: Peter Dimov (pdimov_at_[hidden])
Date: 2004-06-03 06:32:25

Peter Danford wrote:
> By introducing the tss into the thread implementation mentioned
> below, are we gaining functionality so useful it outweighs the
> benefit realized by having a static option available?

This is a question we better not get into. ;-)

A brief history. At first, Boost.Threads supported static linking. It used a
helper DLL (threadmon.dll) to implement TSS cleanup on Windows. At that time
I suggested to Bill Kempf that (a) it might be useful to isolate the
mechanism in a dedicated "at_thread_exit" function exported by
threadmon.dll, thereby allowing users to implement their own cleanup (or to
omit it entirely if they know that their application does not continually
create and destroy threads) and (b) that if Boost.Threads is implemented
itself as a DLL (as pthreads-win32 is) there would be no need for a separate
threadmon.dll.

Now obviously (b) without (a) - the current status quo - is somewhat
problematic for people that don't like DLLs or the DLL runtime (of which I
am one). So I think that we ought to implement (a) as well; statically
linking to Boost.Threads would then result in an unresolved reference to
at_thread_exit, expecting a suitable definition from the user (or from
at_thread_exit.dll, which we'd also supply). The DLL version of
Boost.Threads should, of course, continue to work out of the box, with no
user intervention required.

It is very unfortunate that Bill is no longer active, or even reachable for
comment. I wonder what happened to him.