[boost] call_once on win32

From: Anthony Williams (anthony_w.geo_at_[hidden])
Date: 2005-09-07 10:14:33

I just committed a new version to CVS; pretty much the last version I posted
with void return, but incorporating John Maddock's changes for generating the
name so as to not require std::stringstream, or even strstream.

This version is header only, in contrast to the older version (and current
versions for other platforms), which required a C++ file. This allows the
call_once function to be a template. Note, that windows.h *is not included*
--- explicit prototypes are included for the required functions, following the
lead of boost/detail/interlocked.hpp (which has been updated to include
InterlockedExchange).

Despite tendering a version that handles non-void returns, I am not sure how
to do it right (destruction order for statics makes it hard), so I have left
that out for now.

Anthony
-- 
Anthony Williams
Software Developer