ifstream datafile("myfile.bin", ios_base::in|ios_base::binary);
vector<char> buff;
int size = datafile.tellg();
buff.resize(size);

datafile.read(buff.data(), size);

for (vector<char>::iterator it = buff.begin(); it != buff.end(); ++it)
{
  if (*it == 0x1B)
  {
    // found ESC char
  }
}