Based on the original patch form Vladislav Vaintroub:
http://lists.mysql.com/commits/105379


  @ client/mysql.cc
  - introducing new function tee_write(), to reuse
    in a number of places where similar loops displaying
    data occurs.
  - introducing flags for tee_write(), to support different
    printing modes, according to --xml, --raw, --tab, etc,
    parameters
  - Instead if using argv (which is always in ANSI code page),
    we now use UTF16LE API to access command line arguments on Windows,
    using this scenario:
    a. We translate arguments to UTF8MB4 on startup.
    b. Then we process arguments and detect connection character set
       from --default-character-set arguments (or my.ini value),
       or from the OS localization information by default.
    c. Then we convert user, database and the --execute (-e) buffer
       from UTF8MB4 to the connection character set.
    d. Connect
  - Instead of printing using printif/fputs family functions on Windows,
    which are limited to the current DOS code page (cp850 on a Western machine)
    we now use UTF16LE console API through the new my_win_console_xxx() 
    functions implemented in my_conio.c
  - Using mysql_set_character_set() instead of
    mysql_option(OPT_CHARACTER_SET_NAME) to know the ongoing
    session character set *before* mysql_real_connect() call,
    to convert user and database properly.
  - my_win_is_console_cached() has been added to cache
    my_win_is_console() result for stdout and stderr,
    for performance purposes.

  @ client/mysqltest.cc
  - Introducing a new mysqltest command: --execw, to 
    execute commands with non-ASCII characters correctly in Windows.


  @ include/my_sys.h
  - Adding prototypes for the my_win_console_xxx() functions

  @ mysql-test/grant.test
  @ mysql-test/t/mysql.test
  @ mysql-test/t/mysql_cp932.test
  @ mysql-test/t/mysqlbinlog-cp932.test
  - Using --execw instead of --exec for the affected tests

  @ mysys/my_conio.c
  - Implementing functions for Windows console read/write and
    command line argument processing.
  - Removing my_cgets(), as it's not used any more.

  @ sql-common/client.c
  - Fixing mysql_set_character_set() to set mysql.charset on
    a non-connected "mysql". Previously such a call crashed.
    This change allows to know what character set for the
    ongoing session is going to be *before* calling mysql_real_connect().
    This is needed in mysql.cc, to convert user and database correctly
    on Windows.