@mainarray=("D:");
sub indexcurrent;
indexcurrent("D:");
writefile();

sub indexcurrent
{
   if(opendir(DIR,$_[0]))
   {
    local @current=readdir(DIR);
        for($i=0;$i<=$#current;$i++)
        {
            //this if is because the readdir function   
            //returns "." and ".." also as folders
            if(($current[$i] ne "..")&&($current[$i] ne "."))
            {
                $temp=$current[$i];
                $current[$i]="$_[0]\\$temp";  
\\Here i append the file name with current folder location
                push @mainarray,$current[$i];
                indexcurrent($current[$i]);
            }
        }
   }
}
//to write the array of indexed files into a file
sub writefile
{
    open(File,">E:\\project\\index.txt");
    print File join("\n",@mainarray);
    close (File);
}
print "complete";
<>