Thanks. Here is the code again. I looked into LWP::Parallel. It seems it's not supported in ActivePerl on windows platform. Is there another way I can accomplish the same thing?

use HTTP::Request::Common;
use HTML::Parser;
use HTML::TreeBuilder;
use LWP::UserAgent;
use URI::URL;

@longurl = ('http://1.htm', 'http://2.htm', 'http://3.htm');
@longfie = ('PostData1', 'PostData2', 'PostData3');
$sitetotal=2;
my $pid = fork;
for ($sitenum=0; $sitenum <= $sitetotal; $sitenum++) {
  if ($pid = fork) { next; }
  if (defined $pid) {
    $ua[$sitenum] = new LWP::UserAgent;
    $ua[$sitenum]->timeout(4);
    $res[$sitenum] = $ua[$sitenum]->request(POST $longurl[$sitenum], C
+ontent => [ DataField => "$longfie[$sitenum]" ] );
    if ($res[$sitenum]->is_success) {
      $p[$sitenum]->parse($res[$sitenum]->content);
    }
    $base = $res[$sitenum]->base;
    $siten = $longsite[$sitenum];
    $p[$sitenum]->traverse(\&extract_alinks, 1);
    exit;
  }
  else {
    die "Fork failed at number $sitenum: $!\n"; 
  }
}
$returnstring;

sub extract_alinks1
{
  #extract links and add to $returnstring
}
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