How do I print to the debug output window in a Win32 app?

You can use OutputDebugString. OutputDebugString is a macro that depending on your build options either maps to OutputDebugStringA(char const*) or OutputDebugStringW(wchar_t const*). In the later case you will have to supply a wide character string to the function. To create a wide character literal you can use the L prefix:

OutputDebugStringW(L"My output string.");

Normally you will use the macro version together with the _T macro like this:

OutputDebugString(_T("My output string."));

If you project is configured to build for UNICODE it will expand into:

OutputDebugStringW(L"My output string.");

If you are not building for UNICODE it will expand into:

OutputDebugStringA("My output string.");

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