Simple Binary File I/O Read and Write

So.... I haven't programmed in C++ for over a year (focused on other things) so to get back into the hang of things I just decided to make some real simple binary file i/o stuff.

It writes bytes, words and dwords to a specified offset in a file and will read whatever you want. Not idiot-proof, as in it will probably crash if you do something stupid.

main.cpp

Code:

#include "fileIO.h"
//just a test program
int main()
{
	cout << "WritesBytes version 1.0\nEnter file name:";
	fstream FILE;
	string filename;
	cin >> filename;

	FILE.open(filename.c_str(), ios::in | ios::out | ios::binary);
	writeData16(FILE,0x2A,50000);
	cout << "Wrote:" << readData(FILE,0x2A,word) << '\n';

	cin>> filename;
	FILE.close();
	return 0;
}

fileIO.h

Code:

#ifndef FILEIO_H
#define FILEIO_H

#include <windows.h>
#include <iostream>
#include <fstream>
#include <string>

//codes
#define byte 0
#define word 1
#define dword 2

using namespace std;

typedef DWORD int32;
typedef WORD int16;
typedef BYTE int8;

void writeData32(fstream&, int, int32);
void writeData16(fstream&, int, int16);
void writeData8(fstream&, int, int8);
int readData(fstream&, int, int);

#endif

fileIO.cpp

Code:

#include "fileIO.h"

void writeData32(fstream& File, int location, int32 data)
{
	if(File.is_open() == false)
	{
		cout << "Enter file:";
		string temp; cin >> temp;
		File.open(temp.c_str(), ios::in | ios::out | ios::binary);
		if(!File) { cout << "File Error. Exiting.\n"; exit(1); } //won't bother troubleshooting
	}
	File.seekp(location); //point to the location to write
	File.write((char*)&data,sizeof(int32)); //writes data, specifies 4 bytes to be written
}

void writeData16(fstream& File, int location, int16 data)
{
	if(File.is_open() == false)
	{
		string temp; cin >> temp;
		File.open(temp.c_str(), ios::in | ios::out | ios::binary);
		if(!File) { cout << "File Error. Exiting.\n"; exit(1); } //won't bother troubleshooting
	}
	File.seekp(location); //point to the location to write
	File.write((char*)&data,sizeof(int16)); //writes data, specifies 2 bytes to be written

}

void writeData8(fstream& File, int location, int8 data)
{
	if(File.is_open() == false)
	{
		string temp; cin >> temp;
		File.open(temp.c_str(), ios::in | ios::out | ios::binary);
		if(!File) { cout << "File Error. Exiting.\n"; exit(1); } //won't bother troubleshooting
	}
	File.seekp(location); //point to the location to write
	File.write((char*)&data,sizeof(int8)); //writes data, specifies 1 byte to be written
}

int readData(fstream& File, int location, int size)
{
	int value;
	if(File.is_open() == false)
	{
		string temp; cin >> temp;
		File.open(temp.c_str(), ios::in | ios::out | ios::binary);
		if(!File) { cout << "File Error. Exiting.\n"; exit(1); } //won't bother troubleshooting
	}
	File.seekp(location); //point to location to read from
	if(size == byte)
		File.read((char*)&value,sizeof(int8));
	else if(size == word)
		File.read((char*)&value,sizeof(int16));
	else
		File.read((char*)&value,sizeof(int32));
	return value;
}

Simple Binary File I/O Read and Write

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