This one works without specifying IP address binding.

Changes:

• changed 'Porto' to 'Proto'
• Port changed to 8081 (My machine already used 8080)
• Global $sock localized
• Added "print $new_sock" to send something back (2-way communication)
• Added peer port and IP info
• Improved error messaging (added $!)
• Closed $new_sock
• Removed old-style sub prototyping :sub(){}
• I could not figure out why you had "..or die...unless $sock", so I took out the "unless $sock"

#!/usr/bin/perl -w

use strict;
use warnings;

use IO::Socket::INET;

my $sock = startListening();
close ($sock);

sub startListening{
    my $sock = new IO::Socket::INET( LocalPort => '8081',Proto => 'tcp
+',Listen => '1', Reuse => '1') 
       or die "ERROR: Could not create socket.\n$!";
    my $new_sock  = $sock->accept() or die "ERROR:Lost connection:";

        print "Received incoming connection from " .$new_sock->peerhos
+t () . ", remote port "
               . $new_sock->peerport() . "\n";
        print $new_sock "Ave, Mundus!\n";
        close $new_sock or warn "Could not close new sock:$!";
    return $sock;
}
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