How to create an anti-virus using c++

           HOW TO CREATE AN ANTI-VIRUS USING C++

                                                                   -Today here i'am going to show you how to create an anti-virus by using c++,So let's go to the coding part:-

#include <dirent.h>
#include <string.h>
#include <fstream.h>
#include <conio.h>
#include <stdio.h>
#include <stdlib.h>
#include <iostream.h>

int scan_this(char *file_name)
{
char *pattern, *line_in_file;
char file_ch, ch;
int val, val2, flag;
ifstream fin3, fin4;
fin3.open(file_name); // incase the file is not accesible
if(!fin3) return 0;

else // file is accessible | 100% it is a file.
{
//Opening Virus Database File
fin4.open("db.txt"); // this is our character pattern file

for(;;)
{
fin4>>pattern;
if(!strcmp(pattern,"<-"))
{
fin4>>pattern;
if(!strcmpi(pattern,"End"))return -1;
else if(!strcmpi(pattern, "virus"))
{
if(flag) return 1;
else continue;
}
}
else if(!strcmpi(pattern,"LINE"))
{
fin4>>val; // got the line number

// skipping initial lines to reach the line number
for(int i=0;i<val-1;i++)
{
fin3.getline(line_in_file, 300);
}

fin4>>val; // got the character number
fin4>>file_ch; // got the character

//skipping initial character to reach the character
for(i=0;i<val-1;i++)
{
fin3.get(ch);
}

if(file_ch == ch) flag = 1; // matched.
else flag =0;
fin3.seekg(0); // set to start
}
}

}

}

void main()
{
char comm[300], dirpath[100], file_name[200];
char ask;
int response;
ifstream fin;

cout<<"Enter Directory you want to scan: ";
cin>>dirpath;

strcpy(comm, "dir ");
strcat(comm, "dirpath /b /s >tmp.$$$");
system(comm);

fin.open("tmp.$$$");

while(!fin.eof())
{
fin.getline(file_name, 200);
response = scan_this(file_name);
if(response == 1)
{
cout<<"<–!! Caution.! A Virus has been Detected..!";
cout<<"\n"<<file_name;
cout<<"\nPress Enter Key to Delete it.";
ask= getch();
if(ask == 13)
{
remove(file_name); // delete the virus
}
}
}

fin.close();
cout<<"Scan Complete.!! Thank You for using our anti virus";
getch();

}