using xlocale to implement std::locale class

[Paolo Carlini]

Hi,
>> I don't think I know how to implement the test case, perhaps François.
> I will have a try.
I would really appreciate that. For the record - while working on other 
issues - I quickly tried your testcase and Sam's and had problems, the 
tests failed for me. In particular, I don't know whether is the whole 
story, I guess we have some sort of problem with the standard open, vs 
the one taking an additional dir argument.

Paolo.