Ok,fine. Then include the threads module into your code as

use threads;

within the while loop,create new thread for each domain name.

while ($line = $sth->fetchrow_array()) {
#Your code goes here
my $new_thread = threads->new(\&scan_domain, $line);</b>
} 
sub scan_domain {

        my $domain_name = shift;
        print "started thread for $domain_name\n";
        my @list =`nmap $line`;
        
        foreach(@list){      
        if($_=~/open/g){
            $_ =~ s/\/.*//g;
            if($myport)
            {$myport=$myport.','.$_;chomp $myport;} 
            else{$myport=$_; chomp $myport} 
        }

[download]

Even you can return the $myport from the subroutine and update the table outside the subroutine or even you can have that table updating script inside the subroutine, its your wish.

If you want these threads to run as daemon process do not return from the subroutine use infinite loop to process in a frequent time.

Update:

Included threads cpan link

In reply to Re^3: how to write thread which was multithreaded port scan scripts for nmap by vinoth.ree
in thread how to write thread which was multithreaded port scan scripts for nmap by Anonymous Monk

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