CC: Mr. Wakely

To our WG21 colleagues, please find attached for your information WG14
N2830 fopen('x') and fopen('a') which proposes strengthened wording for
those two operations, which in turn may affect C++ iostreams.

I would once again ask that a maintainer of Microsoft's UCRT get in
touch, as theirs is the only implementation of fopen('a') which I
reviewed which is not atomic (and for no good reason, as Win32
implements it perfectly well).

Niall