Why writing to //./PhysicalDrive0 with _sopen_s() not working

I'm trying to write to physical disk using Microsoft C's _sopen_s() function but it doesn't work at all. Here is my code:

Code-Listing 1:

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <share.h>
#include <fcntl.h>
#include <io.h>

int main(int argc, char * argv[])
{

    int drive_descriptor;

    if((errno = _sopen_s(&drive_descriptor,"//./PhysicalDrive0", _O_RDWR, _SH_DENYNO, _S_IREAD | _S_IWRITE)) != 0)
    {
        printf("Failed to open //./PhysicalDrive0 for writing : %s\n", strerror(errno));
        exit(EXIT_FAILURE);
    }

    return(EXIT_SUCCESS);
}

When I compile and run the code I get, as administrator :

Failed to open //./PhysicalDrive0 for writing : Invalid argument

And without the administrator privilege I get :

Failed to open //./PhysicalDrive0 for writing : Permission denied

I know writing to physical drive can be done because I found a C code that does the work online :

Code-Listing 2:

#include <windows.h>
#include <conio.h>
#include <stdio.h>

void main(){
    DWORD dw;
    char *pathToBin = "C:\\Users\\M\\Desktop\\data.bin";
    HANDLE drive = CreateFile("\\\\.\\I:", GENERIC_ALL, FILE_SHARE_READ | FILE_SHARE_WRITE, 0, OPEN_EXISTING, 0, 0);
    if (drive != INVALID_HANDLE_VALUE){
        HANDLE binary = CreateFile(pathToBin, GENERIC_READ, 0, 0, OPEN_EXISTING, 0, 0);
        if (binary != INVALID_HANDLE_VALUE){
            DWORD size = GetFileSize(binary, 0);
            if (size > 0){
                byte *mbr = new byte[size];
                if (ReadFile(binary, mbr, size, &dw, 0)){
                    printf("Binary file successfuly read!\n");
                    //ok,not lets write the contents of the binary file,to the first sector of the drive
                    if (WriteFile(drive, mbr, size, &dw, 0)){
                        printf("First sector overritten successfuly!\n");
                    }
                    else
                        printf("Fatal error! Can't override 1st sector!\n");
                }
                else
                    printf("Error reading from binary file!\n");
            }
            else
                printf("Invalid binary file!\n");
        }
        else{
            printf("Can't find the binary file to read from!\n");
        }
        CloseHandle(binary);
    }
    else
        printf("Administrator privileges required!\n");
    CloseHandle(drive);
    _getch();
}

I just don't want to use some foreign function that looks too different from what *nix operating systems have (open() function).