As is happens, SVN_DBG which is a test suite friendly SVN debugging tool needed documenting, and it happens to be a very good demonstration of how variadic functions work(esp, if you take time to read the GNU C Preprocessor manual) , and so, danielsh kindly tasked me with writing a small precis that introduces the SVN_DBG tool to new devs in the HACKING GUIDE.
As a nice bonus, it turns out that some time ago, I read over a small, but vital clue of how the ANSI C OO stuff works. I tend to read 'over' some stuff I do not understand in order to keep the universe of confusion minimised, and filed 'va_list' as some funky OO type linked list. So I was quite chuffed at finally figuring out how the 'and here, a miracle occurs' part works -- it uses a variadic function.
This of course calls for an appropriate video:
