How to create an empty file of the specified size in Windows by C++ or C or C#? [closed]

Question

How to create an empty file of the specified size in Windows by C++ or C or C# ?

This file does not take up disk space, Open the file, there isn't anything. But file has number of bytes in the file properties.

For example--

Answer 1

You can do in c++ like this:

#include <iostream>
#include <fstream>
#include <vector>

int main()
{
    std::vector<char> empty(1024, 0);
    std::ofstream ofs("ouput.img", std::ios::binary | std::ios::out);

    for(int i = 0; i < 1024*300; i++)
    {
        if (!ofs.write(&empty[0], empty.size()))
        {
            std::cerr << "problem writing to file" << std::endl;
            return 255;
        }
    }
}

In c#: to make 2GB of file: Simply create the file, seek to a suitably large offset, and write a single byte:

FileStream fs = new FileStream(@"c:\tmp\huge_dummy_file", FileMode.CreateNew);
fs.Seek(2048L * 1024 * 1024, SeekOrigin.Begin);
fs.WriteByte(0);
fs.Close();