MODIF OCTET FICHIER (WIN32)

#include <windows.h>

char *szfile = "D:\\bnMaths.txt"; // ici tu changes

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE, PSTR, int)
{
  DWORD val, myBit;
  HANDLE hfl;
  hfl = CreateFile(szfile, GENERIC_WRITE, 0, 0, OPEN_EXISTING, FILE_FLAG_SEQUENTIAL_SCAN, 0);
  if(hfl == INVALID_HANDLE_VALUE) return 0;
  SetFilePointer(hfl, 8, 0, FILE_BEGIN); // 8 est offset debut, changer
  myBit = 0x41; // a mettre maxi 255, ici est 'A'
  WriteFile(hfl, &myBit, 1, &val, 0);
  CloseHandle(hfl);
  return 0;
}