Listing 11. getservertype3.pl

#!/usr/bin/perl -w
# getservertype3.pl - a threaded version
use strict;
use IO::Socket;
use Thread;
my @hosts = qw(
    www.ssc.com
    www.linuxjournal.com
    www.perl.com
    www.perl.org
    www.nytimes.com
    www.onsight.com
    www.avue.com
);
sub doit {
    my $server = shift;
    print "processing $_...\n";
    my $sock = 
        new IO::Socket::INET(
                PeerAddr => $server,
                PeerPort => 80,
                Proto    => 'tcp');
    $sock or die "no socket for $_: $!";
    print $sock "GET / HTTP/1.0\n\n";
    while (<$sock>) {
	if (/^Server:\s*(.*)/) {
	    print "    $server: $1\n";
	    last;
	}
    }
}
for (@hosts) {
    my $t = new Thread \&doit, $_;
}