Reading Binary Files w/ ifstream - c++

Question

I'm trying to read in an .exe and write it back out. My code works with .txt files but for some reason it is breaking executables. What am I doing wrong?
I'm not sure if I am reading it wrong or writing it wrong..
#include <string>
#include <vector>
#include <iostream>
#include <filesystem>
#include <unordered_set>
#include <Windows.h>
unsigned char *ReadFileAsBytes(std::string filepath, DWORD &buffer_len)
{
std::ifstream ifs(filepath, std::ofstream::binary | std::ifstream::ate);
if (!ifs.is_open())
{
return(nullptr);
}
// Go To End
ifs.seekg(0, ifs.end);
// Get Position (Size)
buffer_len = static_cast<DWORD>(ifs.tellg());
// Go To Beginning
ifs.seekg(0, ifs.beg);
// Allocate New Char Buffer The Size Of File
PBYTE buffer = new BYTE[buffer_len];
ifs.read(reinterpret_cast<char*>(buffer), buffer_len);
ifs.close();
return buffer;
}
void WriteToFile(std::string argLocation, unsigned char *argContents, int argSize)
{
std::ofstream myfile;
myfile.open(argLocation);
myfile.write((const char *)argContents, argSize);
myfile.close();
}
int main()
{
// Config
static std::string szLocation = "C:\\Users\\Admin\\Desktop\\putty.exe";
static std::string szOutLoc = "C:\\Users\\Admin\\Desktop\\putty2.exe";
DWORD dwLen;
unsigned char *szBytesIn = ReadFileAsBytes(szLocation, dwLen);
std::cout << "Read In " << dwLen << " Bytes" << std::endl;
// Write To File
WriteToFile(szOutLoc, szBytesIn, dwLen);
system("pause");
}

Answer 1

You open input file in binary mode, but in this code
std::ofstream myfile;
myfile.open(argLocation);
you open output file without binary mode. And there is no reason to call open separately:
std::ofstream myfile( argLocation, std::ios::out | std::ios::binary | std::ios::trunc);