Get File Size with Kernel32 Api and Ntdll Api (Native Api)

#pragma comment(lib, "ntdll.lib") 

#include <Windows.h>
#include <winternl.h>

#define FileStandardInformation 5

typedef struct _FILE_STANDARD_INFORMATION {
 LARGE_INTEGER AllocationSize;
 LARGE_INTEGER EndOfFile;// file size
 ULONG         NumberOfLinks;
 BOOLEAN       DeletePending;
 BOOLEAN       Directory;
} FILE_STANDARD_INFORMATION, *PFILE_STANDARD_INFORMATION;

BOOL GetFileSizeNtdll(PCWSTR path, PLARGE_INTEGER pFSize)
{
 UNICODE_STRING pathUniStr;
 OBJECT_ATTRIBUTES obja;
 IO_STATUS_BLOCK iost;
 HANDLE hFile;
 FILE_STANDARD_INFORMATION fileStInfo;

 RtlDosPathNameToNtPathName_U(path, &pathUniStr, NULL, NULL);
 InitializeObjectAttributes(&obja, &pathUniStr, OBJ_CASE_INSENSITIVE, NULL, NULL);
 if (!NT_SUCCESS(NtCreateFile(&hFile, FILE_READ_ATTRIBUTES | SYNCHRONIZE, &obja, &iost, NULL, 0, 0, FILE_OPEN, 0, NULL, 0)))
  return FALSE;
 if (!NT_SUCCESS(NtQueryInformationFile(hFile, &iost, &fileStInfo, sizeof(fileStInfo), FileStandardInformation)))
  return FALSE;
 *pFSize = fileStInfo.EndOfFile;
 NtClose(hFile);
}
BOOL GetFileSizeKernel32(PCWSTR path, PLARGE_INTEGER pFSize)
{
 HANDLE hFile;
 BOOL ret;
 if ((hFile = CreateFileW(path, FILE_READ_ATTRIBUTES | SYNCHRONIZE, 0, NULL, OPEN_EXISTING, 0, NULL)) == INVALID_HANDLE_VALUE)
  return FALSE;
 ret= GetFileSizeEx(hFile, pFSize);
 CloseHandle(hFile);
 return ret;
}
int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow)
{
 LARGE_INTEGER fSize1,fSize2;

 //Method 1
 GetFileSizeKernel32(L"C:\\Users\\la\\Desktop\\test.txt",&fSize1);

 //Method 2
 GetFileSizeNtdll(L"C:\\Users\\la\\Desktop\\test.txt", &fSize2);
 return 0;
}

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