[PATCH v2] msvcrt: Use mbtowc/wctomb for string conversion in printf.

[Piotr Caban]

This changes printf behaviour for C locale.

Signed-off-by: Piotr Caban 
---
v2:
  - fix test failures

dlls/msvcrt/msvcrt.h       |  2 +
  dlls/msvcrt/printf.h       | 97 ++++++++++++++++++++++++--------------
  dlls/msvcrt/tests/printf.c | 12 +++++
  3 files changed, 75 insertions(+), 36 deletions(-)