学步园

方法如下：

    #include <windows.h>  
    #include <tchar.h>  
      
    typedef BOOL (WINAPI *LPFN_ISWOW64PROCESS) (HANDLE, PBOOL);  
      
    LPFN_ISWOW64PROCESS fnIsWow64Process;  
      
    BOOL IsWow64()  
    {  
        BOOL bIsWow64 = FALSE;  
      
        //IsWow64Process is not available on all supported versions of Windows.  
        //Use GetModuleHandle to get a handle to the DLL that contains the function  
        //and GetProcAddress to get a pointer to the function if available.  
      
        fnIsWow64Process = (LPFN_ISWOW64PROCESS) GetProcAddress(  
            GetModuleHandle(TEXT("kernel32")),"IsWow64Process");  
      
        if(NULL != fnIsWow64Process)  
        {  
            if (!fnIsWow64Process(GetCurrentProcess(),&bIsWow64))  
            {  
                //handle error  
            }  
        }  
        return bIsWow64;  
    }  
      
    int main( void )  
    {  
        if(IsWow64())  
            _tprintf(TEXT("The process is running under WOW64.\n"));  
        else  
            _tprintf(TEXT("The process is not running under WOW64.\n"));  
      
        return 0;  
    }  

注意，是判断当前操作系统，不是判断CPU

不能通过 #ifdef _WIN64 来判断，因为如果开发环境中定义了该宏，则该判断永远为真

参考：

http://msdn.microsoft.com/en-us/library/windows/desktop/ms684139%28v=vs.85%29.aspx