Read bytes from file and then Output to a std::string

[SwissProgrammer]

Using Windows, CodeBlocks 17.12, GCC 5.1 .

I have a file that I created in C++ and I added a byte order mark to the start of the file.

I read from that file and I am able to read the first byte of that file giving me the first part of that BOM (which I know is there since I put it there).

I would like to place what I read into a std::string to ALSO show up on my CLI output.

Like this:

std::string SS22;
// Get the SS22
// Output the SS22.

I do not just want an output. I want it to be from a std::string.

Here is my code:

#ifndef _UNICODE
    #define _UNICODE    // used by Windows headers,
#endif // _UNICODE

#ifndef UNICODE
    #define UNICODE     // used by C-runtime/MFC headers.
#endif // UNICODE

#include <stdio.h>
#include <iostream>

#include <cstddef>
#include <bitset>

#include <vector>


#include <iostream>
#include <cstdio>
#include <fstream>
#include <sstream>
#include <iomanip>

#include <string.h>

//#include <locale>



using namespace std;


// Since I am using C++11 and I want to use std::byte
using namespace std;


// Since I am using C++11 and I want to use std::byte
namespace std
    {
        // define std::byte
        enum class byte : unsigned char {};
    };


int main()
    {

        std::string FileName;
        FileName = "Some_utf8_Text_With_ByteOrderMark.txt";

        std::cout << "\n\n\nReading  " << FileName << "\n";
        std::cout << "Contents are: [Byte Order Mark BOM] then [hello - こんにちは - abc]\n";
        std::cout << "The BOM is an unsigned char BOM01[3]{ 0xef, 0xbb, 0xbf }\n";
        std::cout << "So, I should see as the first byte: [0xef]\n\n";

        const char * CCP_FileName = FileName.c_str();

        std::FILE *fp;

        unsigned char data;

        std::ifstream("VerifiedToHave_utf8_ByteOrderMark03.txt");

        fp = std::fopen("VerifiedToHave_utf8_ByteOrderMark03.txt", "r");

            fread(&data, 1, 1, fp);

        fclose(fp);

        //The BOM is an unsigned char BOM01[3]{ 0xef, 0xbb, 0xbf }

        std::cout << "Now testing to get the Hex of the first byte in two different ways:\n";

        std::cout << "   test 1  Hex = [" << std::hex << static_cast<int>(static_cast<unsigned char>(data)) << "]\n";
            // [ef]
        std::cout << "   test 2  Hex = [" << std::hex << static_cast<unsigned int>(static_cast<unsigned char>(data)) << "]\n";
            // [ef]


        // Hex ef = binary 11101111
        // Hex bb = binary 10111011
        // Hex bf = binary 10111111

        std::cout << "Attempting to convert the first byte to binary:\n";


        std::cout << "   test 3  Binary   = [";

        bool BolBit[8];

        // fill data
        for(int i = 0; i < 8; i++)
            {
                BolBit[i] = ((data >> i) & 0x01);
                std::cout << BolBit[i];
            }

        std::cout << "]\nThat should have been [11110111]\n\n";
        // 11110111

        std::cout << "Now how do I place that in a std::string?\n\n";



// I tried this but it gives me an error that I have not managed to fix.

//        char s24[sizeof( data ) + sizeof( ( char )'\0' )] = { '\0' };
//        // memcpy (void*, const void*, size_t);
//
//        memcpy( s24, data, sizeof( data ) );
//        // error: invalid conversion from 'unsigned char' to 'const void*' [-fpermissive]
//
//
//        puts( s24 );


        cin.clear();

        cout << "Click the Exit button.\n";

        string s;
        cin >> s;

    }

Here is my current output via CLI.



Reading Some_utf8_Text_ With_ByteOrderM ark.txt
Contents are: [Byte Order Mark BOM] then [hello - πüôπéôπü½πü íπü» - abc]
The BOM is an unsigned char BOM01[3]{ 0xef, 0xbb, 0xbf }
So, I should see as the first byte: [0xef]

Now testing to get the Hex of the first byte in two different ways:
test 1 Hex = [ef]
test 2 Hex = [ef]
Attempting to convert the first byte to binary:
test 3 Binary = [11110111]
That should have been [11110111]

Now how do I place that in a std::string?

Click the Exit button.




I got the ef which is correct.

I got the 11110111 which is correct.

How do I put the ef into a std::string and then output it to the CLI?

How do I put the 11110111 into a std::string and then output it to the CLI?




Thank you.

What am I doing wrong in the code?

What the currect code to use for this?

Thank you.


Later, I plan to convert the second string from a std::string to binary and save it to a new file and see if I can read that new file.


Thank you.