Question

I am attempting to write the following character out in windows command prompt: ｭ (U+FF6D).

I am able to see the character get written out using WriteConsoleW. I am also able to see the character if i use WideCharToMultiByte using the CP_ACP code page (chcp returns 932: Japanese). However, when I attempt to use regular wcout on the same string which WriteConsoleW successfully prints, it chokes.

When I execute setlocale(LC_ALL, “”) it prints English_UnitedStates.1252 (the default code page that I had when I installed).

Why is wcout failing when the others are succeeding?

Note: I rebooted the machine to change its system locale to Japan Japanese

Answer 1

The default locale for C++ iostreams is always the "C" locale. From the C++03 standard, §27.4.2.3/4:

locale getloc() const;

If no locale has been imbued, a copy of the global C++ locale, locale(), in effect at the time of construction.

From §22.1.1.2/1-2:

locale() throw();

Default constructor: a snapshot of the current global locale.

Constructs a copy of the argument last passed to locale::global(locale&), if it has been called; else, the resulting facets have virtual function semantics identical to those of locale::classic().

From §22.1.1.5/4-6:

static const locale& classic();

The "C" locale.

Returns: A locale that implements the classic "C" locale semantics, equivalent to the value locale("C").

Notes: This locale, its facets, and their member functions, do not change with time.

As std::cout and std::wcout have static storage duration, they are guaranteed to be initialized before main is called, and consequently will always have the "C" locale at application startup; i.e., there is no point early enough in execution that one can call locale::global and change the default locale for std::cout and std::wcout. Thus, you must always imbue the global streams yourself if you want to use a non-default code page.