Determine whether it is a 64-bit operating system or a 32-bit System

1. iswow64process: determines whether the specified process runs in a 64-bit 32-bit operating system environment (wow64. Syntax

BOOL WINAPI IsWow64Process(　　__in HANDLE hProcess,　　__out PBOOL Wow64Process　　);

The hprocess handle parameter. This handle must have process_query_information or process_query_limited_information access permission. wow64process points to a bool value. If the process is a 32-bit process and runs in a 64-bit operating system, the value is true. Otherwise, the value is false. If the process is a 64-bit application running on a 64-bit system, the value is also set to false. Return Value: if the function is successful, the return value is a non-zero value. If this function fails, the return value is zero. To obtain the extended error information, call the getlasterror. Microsoft example:

　　#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;　　}

Note: It is not appropriate to use this function to determine whether the operating system is 32-bit or 64-bit. If you want to use this function, you can point to a 32-bit process.

2. The best practice is:

　　BOOL Is64bitSystem()　　{　　　　SYSTEM_INFO si;　　　　GetNativeSystemInfo(&si);　　　　if (si.wProcessorArchitecture == PROCESSOR_ARCHITECTURE_AMD64 ||　　　　　　　　　　　　si.wProcessorArchitecture == PROCESSOR_ARCHITECTURE_IA64 )　　　　　　return TRUE;　　　　else　　　　　　return FALSE;　　}