C / C++ / MFC

const TCHAR* path = _T("C:\\file.dat");
DWORD maxBytesToMap = 64*1024;

// Open the file
HANDLE hFile = ::CreateFile(path, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, 0);

// Get file size for verification
DWORD fileSizeHigh;
DWORD fileSizeLow = ::GetFileSize(hFile, &fileSizeHigh);

// Create the file mapping for the entire file
HANDLE hShMem = ::CreateFileMapping(hFile, NULL, PAGE_READONLY, 0, 0, NULL);

// Create a smaller view at a specific region in the file
// fileOffsetHigh and fileOffsetLow is where the view should begin
unsigned char* pBytes = (unsigned char*)::MapViewOfFile(hShMem, FILE_MAP_READ,
                                 fileOffsetHigh, fileOffsetLow, maxBytesToMap);

// Read data from pBytes
for (size_t i = 0; i < byteCount; ++i)
    x = pBytes[i];

sarfaraznawaz wrote:

1)i tried but not able to understand what actually memory mapped file will do ....

sarfaraznawaz wrote:

2)i also studied in MSDN about this but i not understood the virtual address space ...

sarfaraznawaz wrote:

3)how it will access the data ......

sarfaraznawaz wrote:

one more thing i want ask should i have read the file with Readfile ???

sarfaraznawaz wrote:

one more thing i want to ask that is there any way to hide the folder or file.....

Niklas Lindquist wrote:

The "++ error" comes from the fact that you send a std::string as the third parameter to copy. As the compiler says, std::string has no overloaded ++operator. You should instead use an output_iterator.

Niklas Lindquist wrote:

The name clash problem might come from another header including algorithm. Make use of the namespace qualifiers, and avoid

using namespace std;<br />
<br />
A good idea is to put your own copy function inside a namespace you choose.<br />

#include <string>
#include <iterator>

namespace custom{

	template <class In, class Out> 
	Out copy(  In begin,  In end, Out dest  )
	{
		while ( begin != end ) {

			*dest++ = *begin++ ;
		}	
		
		return dest ;
	}
}





int main() {

	std::string s = "the fox jumped over the moon" ;
	std::string d  ;
	
	custom::copy(  s.begin(), s.end(), std::back_inserter( d  )  );  

        return 0 ;
}

tukbriz wrote:

I'm guessing copy() is overloaded as it exists already in the standard lib.

tukbriz wrote:

*dest++ = *begin++ ;