How to get OS language using C++ API?

I am in the process of developing a application which displays dialogs depending on the OS language. How I can get the OS langua开发者_运维知识库ge using C++ or Windows APIs (Windows 2008/Vista/7)?

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There are several functions to do this in Windows, depending on what format you want the information in. Prior to Windows Vista, the language information was encoded into a LCID (Locale Id) which includes language, as well as some information about sorting and formatting.

For Windows Vista and Windows 7, a more flexible system called Locale Names was devised. GetSystemDefaultLocaleName

Use this if you want to work on Win2k and WinXP. GetSystemDefaultLCID

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The accepted answer to this question is wrong. You should not make user interface decisions based on the default locale. Use GetDefaultUILanguage for this.

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Do you resolve this problem?
If answer is No,
LPWSTR lpLocalName=NULL is wrong.
LPWSTR lpLocalName=NULL ----> WCHAR localName[LOCALE_NAME_MAX_LENGTH] is right. Because No memory allocation is in GetUserDefaultLocalName.