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function GetOSLanguage: string;
var
  LanguageID:LangID;
  Language: array [0..100] of char;
begin
  LanguageID:=GetSystemDefaultLangID;
  VerLanguageName(LanguageID,Language,100);
  Result:=String(Language);
end;

If GetOSLanguage = '?????Deutsch' then					

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function GetOSLanguage: string;
begin
  SetLength(Result,MAX_PATH);
  SetLength(Result,VerLanguageName(GetSystemDefaultLangId,
    @Result[1],length(Result)));
end;					

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var
  buf : array[0..MAX_PATH]of char;
begin
  ZeroMemory(@buf,sizeof(buf));
  GetLocaleInfo(LOCALE_USER_DEFAULT,LOCALE_SABBREVLANGNAME,buf,sizeof(buf));
  MessageBox(0,buf,'Your locale ID is',0);
end.