How to read a byte and save ASCII value of byte in integer in c++

Couple of suggestions:

• Check if the file has actually been opened. If it wasn't, ensure the file is in the current dir, or supply the full path.
• You probably want ios::in (not ios::out).
• Use noskipws unless you actually want to skip whitespaces.
• What's the purpose of returning the character? The convention is to interpret a non-zero exit code as a failure (though admittedly, there is no strict standard on this).

The following program reads the 4th character and prints its HEX value just fine for me:

#include <iostream>
#include <fstream>
#include <stdlib.h>

using namespace std;

int main() {

    ifstream myFile("<path>\\example.txt", ios::in | ios::binary);

    if (myFile) {

        unsigned char b;
        myFile.seekg(3) >> noskipws >> b;

        if (myFile) { // File was long enough?
            unsigned int x = b;
            cout << hex << x;
            return EXIT_SUCCESS;
        }

    }

    return EXIT_FAILURE;

}

(Replace <path> with actual path.)

Try reading using ifstream::read instead of operator>>. This has worked for me:

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

int main(){
  unsigned int x;
  unsigned char b;
  ifstream myFile ("example.txt", ios::out | ios::binary);
  myFile.seekg (0, ios::beg);
  myFile.read(reinterpret_cast<char*>(&b), sizeof(b));
  x = (unsigned int)b;
  cout << hex << x;
  return b;
}