use strict;
use warnings;
use threads;

use IO::Handle qw( );    # Not needed in Perl 5.12+
use Socket     qw( AF_UNIX SOCK_STREAM PF_UNSPEC );

sub socketpipe {
    socketpair($_[0], $_[1], AF_UNIX, SOCK_STREAM, PF_UNSPEC)
        or return undef;
    shutdown($_[0], 1);  # No more writing for reader
    shutdown($_[1], 0);  # No more reading for writer
    $w->autoflush(1);
    return 1;
}

socketpipe(my $r, my $w)
   or die($!);

async {
   print while <$r>;
};

async {
   print($w "abc\n");
   sleep(3);
   print($w "def\n");
   shutdown($w, 1);
};

$_->join for threads->list;