#!perl -w

use strict;
use IO::Select;
use Socket;
use POSIX;


socketpair(SOCK_READ,SOCK_WRITE,AF_UNIX,SOCK_STREAM,PF_UNSPEC)
    or die "Couldn't create socket pair: $!\n";

print "STDOUT print 1.\n";
if (!defined(my $f = fork()))
{
    die "Fork error: $!\n";
}
elsif (!$f)
{
    # child
    close(SOCK_READ);
    warn "CHILD PID: $$\n";
    close(STDOUT)
	or die "Couldn't close STDOUT: $!\n";
    POSIX::dup2(fileno(SOCK_WRITE),1);
    sleep(100)
	while(1);
}
# parent
close(SOCK_WRITE);

warn "Parent is PID $$\n";

# We can't reliably print to STDOUT after this point (at some point,
# it will start going to the socket)

#sleep(5);

print "STDOUT print 2.\n";
my $sel = IO::Select->new;
$sel->add(\*SOCK_READ)
    or die "Couldn't add pipe to IO::Select: $!\n";

print "STDOUT print 3.\n";
while (1)
{
    print "STDOUT print 4.\n";
    warn "DEBUG: select on ",$sel->count," handles.\n";
    my @ready = $sel->can_read(10);
    warn "Parent DEBUG: ",scalar(@ready)," handles readable.\n";
    print "STDOUT print 5.\n";
    foreach my $rh (@ready)
    {
	my $line=<$rh>;
	warn "Parent read $rh: $line";
    }
    sleep(3);
}