C / C++ / MFC

_Flaviu wrote:

pBuffer NULL tell me that I am not able to read that sectors

unsigned char* pBuffer = new unsigned char[dwLen]; // allocate some space for the data to be read into
// or
unsigned char buffer[dwLen]; // allocate on the stack
ReadFile(hVolume, buffer, dwLen, &dwNum, NULL);

unsigned char buffer[dwLen]; // error C2057: expected constant expression

#define SECTOR_SIZE 512
DWORD dwLen = SECTOR_SIZE;
DWORD dwNum = 0;
char buffer[SECTOR_SIZE];
ReadFile(hVolume, buffer, dwLen, &dwNum, NULL);

const int SECTOR_SIZE = 512

CByteArray arrByte;
arrByte.SetSize(512);
BOOL bRet = ReadFile(hVolume, arrByte.GetData(), dwLen, &dwNum, NULL);

file.Open(_T("\\\\.\\F:"), CFile::modeRead | CFile::osSequentialScan); // return FALSE

file.Open(_T("F:"), CFile::modeRead | CFile::osSequentialScan); // return FALSE

file.Open(_T("F:\\"), CFile::modeRead | CFile::osSequentialScan); // return FALSE

	HANDLE hVolume = ::CreateFile(sVolume, GENERIC_READ,
		FILE_SHARE_READ | FILE_SHARE_WRITE, 
		NULL, OPEN_EXISTING, FILE_FLAG_SEQUENTIAL_SCAN, NULL);
	CFile file(hVolume);
	CFileStatus status;
	file.GetStatus(status); // return FALSE

LONG highValue; SetFilePointer(..., ..., &highValue, ...);

LONG lValueLow = 0;
LONG lValueHigh = 0;
if (INVALID_SET_FILE_POINTER == SetFilePointer(hVolume, lValueLow, &lValueHigh, FILE_BEGIN) &&
    NO_ERROR != GetLastError())
{
    TRACE("Error: %d\n", GetLastError());
    return FALSE;
}
else
{
    TRACE("%d\t%d\n", lValueLow, lValueHigh);
}

TestStruct* Funct()
{
    TestStruct* pS = new TestStruct;
    pS->x = 0;
    ps->z = 0;
    // other initialisation code
    
    return pS;
}

//
TestStruct* pNewStruct = Funct();
pNewStruct->x = 100;

// Funct returns a reference on S structure.
   TestStruct& Funct()
   {
       return S;
   }

ChartNode Chart[100];
ChartNode NodeCoord(int x, int z)
{
	return Chart[z * 10 + x];
} 


if(NodeCoord(4,4).access)
//do something 
NodeCoord(4,4).access = false;

void NodeCoord(int x, int z, bool writetobool)
{
 Chart[z * 10 + x].access = writetobool;
}

ChartNode& NodeCoord(int x, int z)
{
     return Chart[z * 10 + x];
}